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Find words whose first and last three letters are equal

From Rosetta Code
Find words whose first and last three letters are equal is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.
Task

Using the dictionary  unixdict.txt

find the words whose first and last three letters are equal.

The length of any word shown should have a length   >  5.


Other tasks related to string operations:
Metrics
Counting
Remove/replace
Anagrams/Derangements/shuffling
Find/Search/Determine
Formatting
Song lyrics/poems/Mad Libs/phrases
Tokenize
Sequences



11l 

L(word) File(‘unixdict.txt’).read().split("\n")
   I word.len > 5 & word[0.<3] == word[(len)-3..]
      print(word)
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

AArch64 Assembly

Works with: as version Raspberry Pi 3B version Buster 64 bits
or android 64 bits with application Termux
/* ARM assembly AARCH64 Raspberry PI 3B */
/*  program Find words whose first and last three letters are equal   */

/*******************************************/
/*         Constantes                      */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM64.inc"
.equ BUFFERSIZE, 300000
.equ WORDSIZE,   5

//.include "../../ficmacros32.inc"        // use for developper debugging
/*******************************************/
/* Structures                          **/
/*******************************************/
/* structure words array  */
    .struct  0
st_word_adr:
    .struct st_word_adr + 8
st_word_size:
    .struct st_word_size + 8
st_word_end:  
/************************************/
/* Initialized data                 */
/************************************/
.data
szMessOpen:           .asciz "File open error.\n"
szMessRead:           .asciz "File read error.\n"
szMessClose:          .asciz "File close error.\n"
szFileName:           .asciz "unixdict.txt"
szMessResult:         .asciz " : "
szCarriageReturn:     .asciz "\n"
szMessStart:          .asciz "Program 64 bits start.\n"
szMessFinOK:          .asciz "Program normal end. \n"
/************************************/
/* UnInitialized data               */
/************************************/
.bss 
sZoneConv:            .skip 24
sBuffer:              .skip BUFFERSIZE     // file buffer
.align 4
WordArray:            .skip st_word_end * 0x10000
/************************************/
/*  code section                    */
/************************************/
.text
.global main   
main:                        // entry of program
    ldr x0,qAdrszMessStart
    bl affichageMess
    ldr x0,qAdrszFileName    // file name
    ldr x1,qAdrsBuffer       // read buffer address
    ldr x2,#iBufferSize      // buffer size
    ldr x3,qAdrWordArray     // word address array
    bl readFile
    cmp x0,#-1               // file error ?
    beq 100f
    mov x2,x0                // word counter
    ldr x0,qAdrsBuffer
    ldr x1,qAdrWordArray     // array address
    bl traitWord

    ldr x0,qAdrszMessFinOK
    bl affichageMess
100:
    mov x0, #0               // return code
    mov x8,EXIT 
    svc 0                    // perform the system call

qAdrsZoneConv:            .quad sZoneConv
qAdrszMessResult:         .quad szMessResult
qAdrszCarriageReturn:     .quad szCarriageReturn
qAdrszMessStart:          .quad szMessStart
qAdrszMessFinOK:          .quad szMessFinOK
qAdrszFileName:           .quad szFileName
qAdrszMessOpen:           .quad szMessOpen
qAdrszMessRead:           .quad szMessRead
qAdrszMessClose:          .quad szMessClose
qAdrsBuffer:              .quad sBuffer
iBufferSize:              .quad BUFFERSIZE
qAdrWordArray:            .quad WordArray
/***************************************************/
/*   read file and create array words                   */
/***************************************************/
/* x0 contains file name */
/* x1 contains a file buffer */
/* x2 contains buffer size */
/* x3 contains array word address */
readFile:
    stp x1,lr,[sp,-16]!
    stp x2,x3,[sp,-16]! 
    stp x4,x5,[sp,-16]! 
    stp x6,x7,[sp,-16]! 
    stp x8,x9,[sp,-16]! 
    mov x9,x1                // file buffer
    mov x6,x2
    mov x1,x0
    mov x10,x3
    mov x0,AT_FDCWD
    mov x2,#O_RDWR           // flags
    mov x3,#0                // mode 
    mov x8,#OPEN             // file open
    svc 0 
    cmp x0,#0                // error ?
    ble 99f
    mov x7,x0                // FD save

    mov x0,x7
    mov x1,x9                // read buffer address
    mov x2,x6
    mov x8,#READ             // call system read file
    svc 0 
    cmp x0,#0                // error read ?
    blt 97f
    mov x6,x0                // save file size
    mov x0,x7                // FD
    mov x8,#CLOSE            // call system close file
    svc 0 
    cmp x0,#0                // error close ?
    blt 96f    
    mov x1,#0                // index buffer
    mov x2,x9                // file buffer address
    mov x3,#0                // word length
    mov x5,#0                // word counter
1:
    ldrb w4,[x9,x1]          // load character file buffer
    cmp x4,#0x0D             // end word ?
    beq 2f                   // yes
    add x1,x1,#1             // increment index and length
    add x3,x3,#1
    b 1b                     // and loop
2:              // 
    strb wzr,[x9,x1]          // store 0 final in word
    cmp x3,#WORDSIZE         // word length  ?
    ble 3f                   // no ?
    mov x0,#st_word_end      // structure size
    madd x0,x5,x0,x10        // compute word item address 
    str x2,[x0,#st_word_adr] // store word address in array word
    str x3,[x0,#st_word_size] // store word size in array word
    add x5,x5,#1             // increment word counter
3:
    add x1,x1,#2             // increment index buffer (0D0A) 
    cmp x1,x6                // end ?
    bge 4f
    add x2,x9,x1             // new word begin
    mov x3,#0                // init word length
    b 1b                     // and loop   
4:
    mov x0,x5                // return word counter 
    b 100f
96:                          // display error messages
    ldr x0,qAdrszMessClose
    bl affichageMess     
    mov x0,#-1               // error
    b 100f
97:
    ldr x0,qAdrszMessRead
    bl affichageMess 
    mov x0,#-1               // error
    b 100f
99:
    ldr x0,qAdrszMessOpen
    bl  affichageMess    
    mov x0,#-1               // error

 100:
    ldp x8,x9,[sp],16
    ldp x6,x7,[sp],16
    ldp x4,x5,[sp],16
    ldp x2,x3,[sp],16
    ldp x1,lr,[sp],16
    ret 



/***************************************************/
/*   word analyse                                  */
/***************************************************/
/* x0 contains a file buffer */
/* x1 contains array word address */
/* x2 contains array element */
traitWord:
    stp x1,lr,[sp,-16]!
    stp x2,x3,[sp,-16]! 
    stp x4,x5,[sp,-16]! 
    stp x6,x7,[sp,-16]! 
    stp x8,x9,[sp,-16]!
    stp x10,x11,[sp,-16]!    
    mov x7,x0               // save buffer address
    mov x8,x1               // save array word address
    mov x9,x2               // save size
    mov x10,#0              // init index word array
    sub sp,sp,#16           // reserve 80 byte on stack for store three byte
    mov fp,sp               // work array address
1:
    mov x0,#st_word_end     // structure size
    madd x0,x10,x0,x8        // compute word item address 
    ldr x11,[x0,#st_word_adr]  // load one word address
    ldr x5,[x0,#st_word_size]  // load word size   
    mov x3,#0               // index word
    sub x6,x5,#3            // index end  word 
2:
    ldrb w4,[x11,x3]        // load characters 
    ldrb w7,[x11,x6]        // load end char
    cmp x4,x7
    bne 10f
    add x6,x6,#1            // increment size new word
    add x3,x3,#1            // increment index
    cmp x3,#3
    blt 2b
    mov x0,x11
    bl affichageMess
    ldr x0,qAdrszCarriageReturn
    bl affichageMess
    
    
10:    
    mov x6,#0                // init new length new word
    add x10,x10,#1           // increment index word array
    cmp x10,x9               // end ?
    blt 1b                   // no -> loop
    
100:
    add sp,sp,#16            // stack alignement release work array  
    ldp x10,x11,[sp],16
    ldp x8,x9,[sp],16
    ldp x6,x7,[sp],16
    ldp x4,x5,[sp],16
    ldp x2,x3,[sp],16
    ldp x1,lr,[sp],16         // TODO: a completer 
    ret

/***************************************************/
/*      ROUTINES INCLUDE                           */
/***************************************************/
/* for this file see task include a file in language ARM assembly*/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeARM64.inc"
Output:
Program 64 bits start.
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes
Program normal end.

Action!

In the following solution the input file unixdict.txt is loaded from H6 drive. Altirra emulator automatically converts CR/LF character from ASCII into 155 character in ATASCII charset used by Atari 8-bit computer when one from H6-H10 hard drive under DOS 2.5 is used. 

BYTE FUNC IsValidWord(CHAR ARRAY word)
  BYTE len

  len=word(0)
  IF len<=5 THEN RETURN (0) FI
  IF word(1)#word(len-2) THEN RETURN(0) FI
  IF word(2)#word(len-1) THEN RETURN(0) FI
  IF word(3)#word(len) THEN RETURN(0) FI
RETURN (1)

PROC FindWords(CHAR ARRAY fname)
  CHAR ARRAY line(256)
  CHAR ARRAY tmp(256)
  BYTE dev=[1]

  Close(dev)
  Open(dev,fname,4)
  WHILE Eof(dev)=0
  DO
    InputSD(dev,line)
    IF IsValidWord(line) THEN
      PrintE(line)
    FI
  OD
  Close(dev)
RETURN

PROC Main()
  CHAR ARRAY fname="H6:UNIXDICT.TXT"

  FindWords(fname)
RETURN
Output:

Screenshot from Atari 8-bit computer 

antiperspirant calendrical einstein hotshot murmur oshkosh tartar testes

Ada 

with Ada.Text_Io;
with Ada.Strings.Fixed;

procedure Find_Three_Equals is
   use Ada.Text_Io;
   use Ada.Strings.Fixed;

   Filename : constant String := "unixdict.txt";
   File     : File_Type;
begin
   Open (File, In_File, Filename);
   while not End_Of_File (File) loop
      declare
         Word  : constant String  := Get_Line (File);
         First : String renames Head (Word, 3);
         Last  : String renames Tail (Word, 3);
      begin
         if First = Last and Word'Length > 5 then
            Put_Line (Word);
         end if;
      end;
   end loop;
   Close (File);
end Find_Three_Equals;

ALGOL 68

Library: ALGOL 68-files

Note, the source of files.incl.a68 is on a separate page on Rosetta Code - see the above link. 

BEGIN # find 6 (or more) character words with the same 3 first and last letters
      #

    PR read "files.incl.a68" PR                      # include file utilities #

    # prints word if it is 6 or more characters long and has the same first   #
    # and last three characters and returns TRUE if printed, FALSE ptherwise  #
    # count so far holds the number of matching words detected so far         #
    PROC show same 3 start and end = ( STRING word, INT count so far )BOOL:
         IF   INT w len = ( UPB word + 1 ) - LWB word;
              w len < 6
         THEN FALSE
         ELIF word[ 1 : 3 ] /= word[ w len - 2 : ]
         THEN FALSE
         ELSE print( ( word, " " ) );
              IF ( count so far + 1 ) MOD 5 = 0
              THEN print( ( newline ) )
              ELSE FROM w len + 1 TO 14 DO print( ( " " ) ) OD
              FI;
              TRUE
         FI # show same 3 start and end # ;

    IF  INT count = "unixdict.txt" EACHLINE show same 3 start and end;
        count < 0
    THEN
        print( ( "Unable to open unixdict.txt", newline ) )
    ELSE
        print( ( newline, "found ", whole( count, 0 ) ) );
        print( ( " words with the same first and last 3 characters" ) );
        print( ( newline ) )
    FI

END
Output:
antiperspirant calendrical    einstein       hotshot        murmur
oshkosh        tartar         testes
found 8 words with the same first and last 3 characters

AppleScript 

on task()
    script o
        property wrds : words of ¬
            (read file ((path to desktop as text) & "www.rosettacode.org:unixdict.txt") as «class utf8»)
        property output : {}
    end script
    
    repeat with thisWord in o's wrds
        if ((thisWord's length > 5) and (thisWord ends with thisWord's text 1 thru 3)) then ¬
            set end of o's output to thisWord
    end repeat
    
    return o's output's contents
end task

task()
Output:
{"antiperspirant", "calendrical", "einstein", "hotshot", "murmur", "oshkosh", "tartar", "testes"}

ARM Assembly

Works with: as version Raspberry Pi
or android 32 bits with application Termux
/* ARM assembly Raspberry PI  */
/*  program Find words whose first and last three letters are equal   */
 
/************************************/
/* Constantes                       */
/************************************/
/* for this file see task include a file in language ARM assembly*/
.include "../constantes.inc"
.equ READ,   3
.equ WRITE,  4
.equ OPEN,   5
.equ CLOSE,  6
.equ O_RDWR,  0x0002         @ open for reading and writing
.equ BUFFERSIZE, 300000
.equ WORDSIZE,   5

//.include "../../ficmacros32.inc"        @ use for developper debugging
/*******************************************/
/* Structures                          **/
/*******************************************/
/* structure words array  */
    .struct  0
st_word_adr:
    .struct st_word_adr + 4
st_word_size:
    .struct st_word_size + 4
st_word_end:  
/************************************/
/* Initialized data                 */
/************************************/
.data
szMessOpen:           .asciz "File open error.\n"
szMessRead:           .asciz "File read error.\n"
szMessClose:          .asciz "File close error.\n"
szFileName:           .asciz "unixdict.txt"
szMessResult:         .asciz " : "
szCarriageReturn:     .asciz "\n"
szMessStart:          .asciz "Program 32 bits start.\n"
szMessFinOK:          .asciz "Program normal end. \n"
/************************************/
/* UnInitialized data               */
/************************************/
.bss 
sZoneConv:            .skip 24
sBuffer:              .skip BUFFERSIZE     @ file buffer
.align 4
WordArray:            .skip st_word_end * 0x10000
/************************************/
/*  code section                    */
/************************************/
.text
.global main   
main:                        @ entry of program
    ldr r0,iAdrszMessStart
    bl affichageMess
    ldr r0,iAdrszFileName    @ file name
    ldr r1,iAdrsBuffer       @ read buffer address
    ldr r2,#iBufferSize      @ buffer size
    ldr r3,iAdrWordArray     @ word address array
    bl readFile
    cmp r0,#-1               @ file error ?
    beq 100f
    mov r2,r0                @ word counter
    ldr r0,iAdrsBuffer
    ldr r1,iAdrWordArray     @ array address
    bl traitWord

    ldr r0,iAdrszMessFinOK
    bl affichageMess
100:
    mov r0, #0               @ return code
    mov r7, #EXIT            @ request to exit program
    svc 0                    @ perform the system call

iAdrsZoneConv:            .int sZoneConv
iAdrszMessResult:         .int szMessResult
iAdrszCarriageReturn:     .int szCarriageReturn
iAdrszMessStart:          .int szMessStart
iAdrszMessFinOK:          .int szMessFinOK
iAdrszFileName:           .int szFileName
iAdrszMessOpen:           .int szMessOpen
iAdrszMessRead:           .int szMessRead
iAdrszMessClose:          .int szMessClose
iAdrsBuffer:              .int sBuffer
iBufferSize:              .int BUFFERSIZE
iAdrWordArray:            .int WordArray
/***************************************************/
/*   read file and create array words                   */
/***************************************************/
/* r0 contains file name */
/* r1 contains a file buffer */
/* r2 contains buffer size */
/* r3 contains array word address */
readFile:
    push {r1-r9,lr}          @ save registers
    mov r9,r1                @ file buffer
    mov r6,r2
    mov r10,r3
    mov r1,#O_RDWR           @ flags
    mov r2,#0                @ mode 
    mov r7,#OPEN             @ file open
    svc 0 
    cmp r0,#0                @ error ?
    ble 99f
    mov r8,r0                @ FD save

    mov r0,r8
    mov r1,r9                @ read buffer address
    mov r2,r6
    mov r7,#READ             @ call system read file
    svc 0 
    cmp r0,#0                @ error read ?
    blt 97f
    mov r6,r0                @ save file size
    mov r0,r8                @ FD
    mov r7,#CLOSE            @ call system close file
    svc 0 
    cmp r0,#0                @ error close ?
    blt 96f    
    mov r1,#0                @ index buffer
    mov r2,r9                @ file buffer address
    mov r3,#0                @ word length
    mov r5,#0                @ word counter
1:
    ldrb r4,[r9,r1]          @ load character file buffer
    cmp r4,#0x0D             @ end word ?
    beq 2f                   @ yes
    add r1,r1,#1             @ increment index and length
    add r3,r3,#1
    b 1b                     @ and loop
2:
    mov r4,#0                @ 
    strb r4,[r9,r1]          @ store 0 final in word
    cmp r3,#WORDSIZE         @ word length  ?
    ble 3f                   @ no ?
    mov r0,#st_word_end      @ structure size
    mla r0,r5,r0,r10         @ compute word item address 
    str r2,[r0,#st_word_adr] @ store word address in array word
    str r3,[r0,#st_word_size] @ store word size in array word
    add r5,r5,#1             @ increment word counter
3:
    add r1,r1,#2             @ increment index buffer (0D0A) 
    cmp r1,r6                @ end ?
    bge 4f
    add r2,r9,r1             @ new word begin
    mov r3,#0                @ init word length
    b 1b                     @ and loop   
4:
    mov r0,r5                @ return word counter 
    b 100f
96:                          @ display error messages
    ldr r0,iAdrszMessClose
    bl affichageMess     
    mov r0,#-1               @ error
    b 100f
97:
    ldr r0,iAdrszMessRead
    bl affichageMess 
    mov r0,#-1               @ error
    b 100f
99:
    ldr r0,iAdrszMessOpen
    bl  affichageMess    
    mov r0,#-1               @ error

 100:
    pop {r1-r9,pc}  
/***************************************************/
/*   word analyse                                  */
/***************************************************/
/* r0 contains a file buffer */
/* r1 contains array word address */
/* r2 contains array element */
traitWord:
    push {r1-r12,lr}        @ save registers
    mov r7,r0               @ save buffer address
    mov r8,r1               @ save array word address
    mov r9,r2               @ save size
    mov r10,#0              @ init index word array
    sub sp,sp,#8            @ reserve 80 byte on stack for store three byte
    mov fp,sp               @ work array address
1:
    mov r0,#st_word_end     @ structure size
    mla r0,r10,r0,r8        @ compute word item address 
    ldr r12,[r0,#st_word_adr]  @ load one word address
    ldr r5,[r0,#st_word_size]  @ load word size   
    mov r3,#0               @ index word
    sub r6,r5,#3            @ index end  word 
2:
    ldrb r4,[r12,r3]        @ load characters 
    ldrb r7,[r12,r6]        @ load end char
    cmp r4,r7
    bne 10f
    add r6,r6,#1            @ increment size new word
    add r3,r3,#1            @ increment index
    cmp r3,#3
    blt 2b
    mov r0,r12
    bl affichageMess
    ldr r0,iAdrszCarriageReturn
    bl affichageMess
    
    
10:    
    mov r6,#0                @ init new length new word
    add r10,r10,#1           @ increment index word array
    cmp r10,r9               @ end ?
    blt 1b                   @ no -> loop
    
100:
    add sp,sp,#8            @ stack alignement release work array  
    pop {r1-r12,pc}     

/***************************************************/
/*      ROUTINES INCLUDE                           */
/***************************************************/
/* for this file see task include a file in language ARM assembly*/
.include "../affichage.inc"
Output:
Program 32 bits start.
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes
Program normal end.

Arturo 

words: read.lines relative "unixdict.txt"
equalHeadTail?: function [w][
    equal? first.n: 3 w last.n: 3 w
]

loop words 'word [
    if 5 < size word [
        if equalHeadTail? word ->
            print word
    ]
]
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

AutoHotkey 

FileRead, db, % A_Desktop "\unixdict.txt"
for i, word in StrSplit(db, "`n", "`r")
    if StrLen(word) < 6
        continue
    else if (SubStr(word, 1, 3) = SubStr(word, -2))
        result .= word "`n"
MsgBox, 262144, , % result
return
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

AWK 

# syntax: GAWK -f FIND_WORDS_WHICH_FIRST_AND_LAST_THREE_LETTERS_ARE_EQUALS.AWK unixdict.txt
(length($0) >= 6 && substr($0,1,3) == substr($0,length($0)-2,3))
END {
    exit(0)
}
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

BQN 

EndsEq ← -⊸↑≡↑

•Show 3 (EndsEq¨/⊢) (5<≠¨)⊸/ •Flines "unixdict.txt"
Output:
⟨ "antiperspirant" "calendrical" "einstein" "hotshot" "murmur" "oshkosh" "tartar" "testes" ⟩

C 

#include <stdio.h>
#include <stdlib.h>
#include <string.h>


/* "Using the dictionary unixdict.txt" */
#define DICTIONARY_FILE_NAME "unixdict.txt"

/* take into account the first and last 3 letters */
#define CHUNK_LENGTH 3

/* "The length of any word shown should be >5" */
#define MIN_WORD_LENGTH 6


char *create_word_buffer( const char *file_name, size_t *buffer_size );
int wait_for_return( void );


int main() {
    size_t buffer_size = 0;
    char *buffer = create_word_buffer( DICTIONARY_FILE_NAME, &buffer_size );

    if( buffer ) {
        FILE *f = fopen( DICTIONARY_FILE_NAME, "r" );

        if( f ) {
            while( fgets(buffer,buffer_size,f) ) {
                size_t l = strlen( buffer );
                if( '\n'==buffer[l-1] ) buffer[--l] = '\0';

                if( l>=MIN_WORD_LENGTH &&
                    0==memcmp(buffer,buffer+l-CHUNK_LENGTH,CHUNK_LENGTH) ) {
                    printf( "%s\n", buffer );
                }
            }

            fclose( f ); f = NULL; /* cleanup */
        } else puts( "Couldn't open dictionary file." );

        free( buffer ); buffer = NULL; /* cleanup */
    } else puts( "Couldn't create word buffer." );

    return wait_for_return();
}


/*==============================================================================
No need to verify any parameters in any of the following function - the caller
did his homeworks.
==============================================================================*/


size_t get_line_length( FILE *f ) {
    size_t line_length = 0;
    int c, ok;

    do {
        c = fgetc(f);
        ok = '\n'!=c&&EOF!=c;
        line_length += ok;
    } while( ok );

    return line_length;
}


size_t find_longest_line_in_file( const char *file_name ) {
    size_t max_line_length = ((size_t)-1);

    FILE *f = fopen( file_name, "r" );

    if( f ) {
        max_line_length = 0;

        while( !feof(f) ) {
            size_t line_length = get_line_length( f );

            if( line_length>max_line_length )
                max_line_length = line_length;
        }

        fclose( f ); f = NULL;
    }

    return max_line_length;
}


char *create_word_buffer( const char *file_name, size_t *buffer_size ) {
    char *buffer = NULL;

    size_t max_line_length = find_longest_line_in_file( file_name );

    if( ((size_t)-1)!=max_line_length ) {
        buffer = calloc( max_line_length+2, sizeof(*buffer) );
        if( buffer ) *buffer_size = max_line_length+2;
    }

    return buffer;
}


int wait_for_return( void ) {
    puts( "\nPress Return to exit...    " );
    while( '\n'!=getchar() );
    return 0;
}
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Press Return to exit...

C++ 

#include <cstdlib>
#include <fstream>
#include <iostream>

int main(int argc, char** argv) {
    const char* filename(argc < 2 ? "unixdict.txt" : argv[1]);
    std::ifstream in(filename);
    if (!in) {
        std::cerr << "Cannot open file '" << filename << "'.\n";
        return EXIT_FAILURE;
    }
    std::string word;
    int n = 0;
    while (getline(in, word)) {
        const size_t len = word.size();
        if (len > 5 && word.compare(0, 3, word, len - 3) == 0)
            std::cout << ++n << ": " << word << '\n';
    }
    return EXIT_SUCCESS;
}
Output:
1. antiperspirant
2. calendrical
3. einstein
4. hotshot
5. murmur
6. oshkosh
7. tartar
8. testes

Delphi

Works with: Delphi version 6.0
Library: SysUtils,StdCtrls

Runs in 13 ms. 

var Dict: TStringList;	{List holds dictionary}


procedure FindFirst3Last3Match(Memo: TMemo);
{Find words where the first and last 3 characters are identical}
var I: integer;
var First3,Last3: string;
begin
for I:=0 to Dict.Count-1 do
 if Length(Dict[I])>5 then
	begin
	First3:=Copy(Dict[I],1,3);
	Last3:=Copy(Dict[I],Length(Dict[I])-2,3);
	if First3=Last3 then
		begin
		Memo.Lines.Add(Dict[I]);
		end
	end;
end;


initialization
{Create/load dictionary}
Dict:=TStringList.Create;
Dict.LoadFromFile('unixdict.txt');
Dict.Sorted:=True;
finalization
Dict.Free;
end.
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

DuckDB

Works with: DuckDB version V1.0

In this entry, the fact that an on-the-fly table can be referenced within a function is used to avoid having to create a named table while still allowing a certain measure of functional abstraction. The alternative would involve using query_table(), which was only introduced in DuckDB 1.1. 

# Use an in-scope dictionary, dictionary(word), as the dictionary
create or replace function same_first_and_last_three_letters() as table (
  FROM dictionary
  WHERE word[:3] = word[-3:]
  ORDER BY word
);

with dictionary as (
  SELECT lower(word) as word
  FROM read_csv('unixdict.txt', header=false, sep='',
                columns={'word': VARCHAR}, auto_detect=false)
  WHERE length(word)>5
)
FROM same_first_and_last_three_letters();
Output:

(elided) 

┌────────────────┐
│      word      │
│    varchar     │
├────────────────┤
│ antiperspirant │
│ calendrical    │
│ einstein       │
│ hotshot        │
│ murmur         │
│ oshkosh        │
│ tartar         │
│ testes         │
└────────────────┘

EasyLang 

repeat
   s$ = input
   until s$ = ""
   l = len s$
   if l > 5
      if substr s$ 1 3 = substr s$ (l - 2) 3
         print s$
      .
   .
.
# the content of unixdict.txt 
input_data
10th
.
einstein
.

ed 

# by Artyom Bologov
H
v/^\(.\)\(.\)\(.\).*\1\2\3$/d
,p
Q
Output:
$ ed -s unixdict.txt < first-last-three.ed 
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes


F# 

// First and last three letters are equal. Nigel Galloway: February 18th., 2021
let fN g=if String.length g<6 then false else g.[..2]=g.[g.Length-3..]
seq{use n=System.IO.File.OpenText("unixdict.txt") in while not n.EndOfStream do yield n.ReadLine()}|>Seq.filter fN|>Seq.iter(printfn "%s")
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Factor

Read entire file

This version reads the entire dictionary file into memory and filters it. This is the fastest version by far. Factor is optimized for making multiple passes over data; it actually takes longer if we combine the two filters into one, either with short-circuiting or non-short-circuiting and. 

USING: io io.encodings.ascii io.files kernel math sequences ;

"unixdict.txt" ascii file-lines
[ length 5 > ] filter
[ [ 3 head-slice ] [ 3 tail-slice* ] bi = ] filter
[ print ] each
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Read file line by line

This version reads the dictionary file line by line and prints out words that fit the criteria. This ends up being a bit more imperative and deeply nested, but unlike the version above, we only load one word at a time, saving quite a bit of memory. 

USING: combinators.short-circuit io io.encodings.ascii io.files
kernel math sequences ;

"unixdict.txt" ascii [
    [
        readln dup
        [
            dup
            {
                [ length 5 > ]
                [ [ 3 head-slice ] [ 3 tail-slice* ] bi = ]
            } 1&&
            [ print ] [ drop ] if
        ] when*
    ] loop
] with-file-reader
Output:

As above.

Lazy file I/O

This version lazily reads the input file by treating a stream like a lazy list with the llines word. This allows us the nice style of the first example with the memory benefits of the second example. Unlike in the first example, combining the filters would buy us some time here, as lazy lists aren't as efficient as sequences. 

USING: io io.encodings.ascii io.files kernel lists lists.lazy
math sequences ;

"unixdict.txt" ascii <file-reader> llines
[ length 5 > ] lfilter
[ [ 3 head-slice ] [ 3 tail-slice* ] bi = ] lfilter
[ print ] leach
Output:

As above.

Forth

Works with: Gforth
: first-last-three-equal { addr len -- ? }
  len 5 <= if false exit then
  addr 3 addr len 3 - + 3 compare 0= ;

256 constant max-line

: main
  0 0 { count fd-in }
  s" unixdict.txt" r/o open-file throw to fd-in
  begin
    here max-line fd-in read-line throw
  while
    here swap 2dup first-last-three-equal if
      count 1+ to count
      count 1 .r ." . " type cr
    else
      2drop
    then
  repeat
  drop
  fd-in close-file throw ;

main
bye
Output:
1. antiperspirant
2. calendrical
3. einstein
4. hotshot
5. murmur
6. oshkosh
7. tartar
8. testes

FreeBASIC 

#define NULL 0

type node
    word as string*32   'enough space to store any word in the dictionary
    nxt as node ptr
end type

function addword( tail as node ptr, word as string ) as node ptr
    'allocates memory for a new node, links the previous tail to it,
    'and returns the address of the new node
    dim as node ptr newnode = allocate(sizeof(node))
    tail->nxt = newnode
    newnode->nxt = NULL
    newnode->word = word
    return newnode
end function

function length( word as string ) as uinteger
    'necessary replacement for the built-in len function, which in this
    'case would always return 32
    for i as uinteger = 1 to 32
        if asc(mid(word,i,1)) = 0 then return i-1
    next i
    return 999
end function

dim as string word
dim as node ptr tail = allocate( sizeof(node) )
dim as node ptr head = tail, curr = head, currj
dim as uinteger ln
tail->nxt = NULL
tail->word = "XXXXHEADER"

open "unixdict.txt" for input as #1
while true
    line input #1, word
    if word = "" then exit while
    if length(word)>5 then tail = addword( tail, word )
wend
close #1

while curr->nxt <> NULL
    word = curr->word
    ln = length(word)
    for i as uinteger = 1 to 3
        if mid(word,i,1) <> mid(word,ln-3+i,1) then goto nextword
    next i
    print word
    nextword:
    curr = curr->nxt
wend
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

FutureBasic 

#plist NSAppTransportSecurity @{NSAllowsArbitraryLoads:YES}

local fn Words as CFArrayRef
  CFURLRef     url       = fn URLWithString( @"http://wiki.puzzlers.org/pub/wordlists/unixdict.txt" )
  CFStringRef  string    = fn StringWithContentsOfURL( url, NSUTF8StringEncoding, NULL )
  CFArrayRef   array     = fn StringComponentsSeparatedByCharactersInSet( string, fn CharacterSetNewlineSet )
  PredicateRef predicate = fn PredicateWithFormat( @"self.length > %d", 5 )
end fn = fn ArrayFilteredArrayUsingPredicate( array, predicate )

void local fn DoIt
  CFArrayRef  words = fn Words
  CFStringRef wd
  for wd in words
    if ( fn StringIsEqual( left(wd,3), right(wd,3) ) )
      print wd
    end if
  next
end fn

fn DoIt

HandleEvents
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Go 

package main

import (
    "bytes"
    "fmt"
    "io/ioutil"
    "log"
    "unicode/utf8"
)

func main() {
    wordList := "unixdict.txt"
    b, err := ioutil.ReadFile(wordList)
    if err != nil {
        log.Fatal("Error reading file")
    }
    bwords := bytes.Fields(b)
    count := 0
    for _, bword := range bwords {
        s := string(bword)
        if utf8.RuneCountInString(s) > 5 && (s[0:3] == s[len(s)-3:]) {
            count++
            fmt.Printf("%d: %s\n", count, s)
        }
    }
}
Output:
1: antiperspirant
2: calendrical
3: einstein
4: hotshot
5: murmur
6: oshkosh
7: tartar
8: testes

J 

   >(#~ ((3&{. -: _3&{.)*5<#)@>) cutLF fread 'unixdict.txt'
antiperspirant
calendrical   
einstein      
hotshot       
murmur        
oshkosh       
tartar        
testes

Java 

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;

public final class FindWordsWhoseFirstAndLastThreeLettersAreEqual {

	public static void main(String[] args) throws IOException {
		Files.lines(Path.of("./unixdict.txt"))
			 .filter( w -> w.length() > 5 && w.substring(0, 3).equals(w.substring(w.length() - 3)))			
			 .forEach( w -> System.out.print(w + " ") );
	}

}
Output:
antiperspirant calendrical einstein hotshot murmur oshkosh tartar testes

jq

Works with: jq

Works with gojq, the Go implementation of jq 

select(length > 5 and .[:3] == .[-3:])
Output:

Invocation example: jq -rRM -f program.jq unixdict.txt 

antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Julia

See Alternade_words#Julia for the foreachword function. 

matchfirstlast3(word, _) = length(word) > 5 && word[1:3] == word[end-2:end] ? word : ""
foreachword("unixdict.txt", matchfirstlast3, numcols=4)
Output:
Word source: unixdict.txt

antiperspirant calendrical    einstein       hotshot
murmur         oshkosh        tartar         testes

Ksh 

#!/bin/ksh

# Find list of words (> 5 chars) where 1st 3 and last 3 letters are the same

#	# Variables:
#
dict='../unixdict.txt'
integer MIN_LEN=5
integer MATCH_NO=3

 ######
# main #
 ######

 while read word; do
	(( ${#word} <= MIN_LEN )) && continue

	first=${word:0:${MATCH_NO}}
	last=${word:$((${#word}-MATCH_NO)):${#word}}

	[[ ${first} == ${last} ]] && print ${word}

 done < ${dict}
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Lambdatalk 

The unixdict.txt has been loaded from https://web.archive.org and stored in a wiki page, lib_UNIXDICT, from which it can be required on demand in any other one.

{require lib_UNIXDICT}

{def look
 {lambda {}
  {S.replace \s by {div} in
   {S.map {lambda {:w} 
           {if {and {> {W.length :w} 5} 
                    {W.equal? {W.slice 0 3 :w}
                              {W.slice -3 {W.length :w} :w} }}
            then :w 
            else}} {S.replace else by el.se in UNIXDICT}} }}}
-> look
 
{look}
-> 
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Note: Due to a "weakness" of the {if then else} special form, where the else separator is not protected, every occurences of the string "else" in the input text must be replaced by some "broken word" before the search, for instance "el.se" and restored after if necessary.

Mathematica /Wolfram Language 

dict = Once[Import["https://web.archive.org/web/20180611003215/http://www.puzzlers.org/pub/wordlists/unixdict.txt"]];
dict //= StringSplit[#, "\n"] &;
dict //= Select[StringLength /* GreaterThan[5]];
Select[dict, StringTake[#, 3] === StringTake[#, -3] &]
Output:
{"antiperspirant", "calendrical", "einstein", "hotshot", "murmur", "oshkosh", "tartar", "testes"}

Nim 

for word in "unixdict.txt".lines:
  if word.len > 5:
    if word[0..2] == word[^3..^1]:
      echo word
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Nu

Works with: Nushell version 0.97.1
open 'unixdict.txt' | split words -l 6 | where $it ends-with ($it | str substring ..2)
Output:
╭───┬────────────────╮
│ 0 │ antiperspirant │
│ 1 │ calendrical    │
│ 2 │ einstein       │
│ 3 │ hotshot        │
│ 4 │ murmur         │
│ 5 │ oshkosh        │
│ 6 │ tartar         │
│ 7 │ testes         │
╰───┴────────────────╯

Perl

as one-liner .. 

// 20210212 Perl programming solution

perl -ne '/(?=^(.{3}).*\1$)^.{6,}$/&&print' unixdict.txt

# minor variation

perl -ne 's/(?=^(.{3}).*\1$)^.{6,}$/print/e' unixdict.txt

Phix 

with javascript_semantics
function flaste(string word) return length(word)>5 and word[1..3]=word[-3..-1] end function
sequence flastes = filter(unix_dict(),flaste)
printf(1,"%d words: %s\n",{length(flastes),join(shorten(flastes,"",3))})
Output:
8 words: antiperspirant calendrical einstein hotshot murmur oshkosh tartar testes

PL/I 

firstAndLast3Equal: procedure options(main);
    declare dict file;
    open file(dict) title('unixdict.txt');
    on endfile(dict) stop;
    
    declare word char(32) varying, (first3, last3) char(3);
    do while('1'b);
        get file(dict) list(word);
        first3 = substr(word, 1, 3);
        last3 = substr(word, length(word)-2, 3);
        if length(word) > 5 & first3 = last3 then
            put skip list(word); 
    end;    
end firstAndLast3Equal;
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Python

Tested on Python 3+, the file download will work only if the link is still active. It is possible that you may be able to fetch the file in your browser but download via code may still fail. Check whether you are connected to a VPN, it works on open networks 

import urllib.request
urllib.request.urlretrieve("http://wiki.puzzlers.org/pub/wordlists/unixdict.txt", "unixdict.txt")

dictionary = open("unixdict.txt","r")

wordList = dictionary.read().split('\n')

dictionary.close()

for word in wordList:
    if len(word)>5 and word[:3].lower()==word[-3:].lower():
        print(word)
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Quackery 

  [ [] swap ]'[ swap
    witheach [
      dup nested
      unrot over do
      iff [ dip join ]
      else nip
    ] drop ]                   is filter ( [ --> [ )

  $ "unixdict.txt" sharefile drop nest$
  filter [ size 5 > ]
  filter [ 3 split -3 split nip = ]
  witheach [ echo$ cr ]
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

R 

dict <- scan("https://web.archive.org/web/20180611003215/http://www.puzzlers.org/pub/wordlists/unixdict.txt", what = character())
dict[nchar(dict) > 5 & substr(dict, 1, 3) == substr(dict, nchar(dict) - 2, nchar(dict))]

Racket 

#lang racket

(define ((prefix-and-suffix-match? len) str)
  (let ((l (string-length str)))
    (and (>= l (* 2 len))
         (string=? (substring str 0 len)
                   (substring str (- l len))))))

(module+ main
  (filter (prefix-and-suffix-match? 3) (file->lines "../../data/unixdict.txt")))
Output:
'("antiperspirant" "calendrical" "einstein" "hotshot" "murmur" "oshkosh" "tartar" "testes")

Raku 

# 20210210 Raku programming solution

my ( \L, \N, \IN ) = 5, 3, 'unixdict.txt';

for IN.IO.lines { .say if .chars > L and .substr(0,N) eq .substr(*-N,*) }
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Red 

Red[]

foreach word read/lines %unixdict.txt [
    if all [
        greater? length? word 5
        equal? take/part copy word 3 take/part/last copy word 3
    ][
        print word
    ]
]
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

REXX

This REXX version doesn't care what order the words in the dictionary are in,   nor does it care what
case  (lower/upper/mixed)  the words are in,   the search for the words and vowels is   caseless.

The program verifies that the first and last three characters are, indeed, letters.

It also allows the length (3) of the first and last number of letters to be specified,   and also the minimum length of the
words to be searched on the command line (CL) as well as specifying the dictionary file identifier. 

/*REXX pgm finds words in an specified dict. which have the same 1st and last 3 letters.*/
parse arg minL many iFID .                       /*obtain optional arguments from the CL*/
if minL=='' | minL=="," then minL=  6            /* "      "         "   "   "     "    */
if many=='' | many=="," then many=  3            /* "      "         "   "   "     "    */
if iFID=='' | iFID=="," then iFID='unixdict.txt' /* "      "         "   "   "     "    */

              do #=1  while lines(iFID)\==0      /*read each word in the file  (word=X).*/
              x= strip( linein( iFID) )          /*pick off a word from the input line. */
              @.#= x                             /*save:  the original case of the word.*/
              end   /*#*/
#= # - 1                                         /*adjust word count because of DO loop.*/
say copies('─', 30)     #     "words in the dictionary file: "       iFID
finds= 0                                         /*word count which have matching end.  */
                                                 /*process all the words that were found*/
     do j=1  for #;          $= @.j;    upper $  /*obtain dictionary word; uppercase it.*/
     if length($)<minL  then iterate             /*Word not long enough?   Then skip it.*/
     lhs= left($, many);     rhs= right($, many) /*obtain the left & right side of word.*/
     if \datatype(lhs || rhs, 'U')  then iterate /*are the left and right side letters? */
     if lhs \== rhs                 then iterate /*Left side match right side?  No, skip*/
     finds= finds + 1                            /*bump count of only "e" vowels found. */
     say right( left(@.j, 30),  40)              /*indent original word for readability.*/
     end        /*j*/
                                                 /*stick a fork in it,  we're all done. */
say copies('─', 30)  finds  " words found that the left "   many   ' letters match the' ,
                            "right letters which a word has a minimal length of "     minL
output   when using the default inputs:
────────────────────────────── 25104 words in the dictionary file:  unixdict.txt
          antiperspirant
          calendrical
          einstein
          hotshot
          murmur
          oshkosh
          tartar
          testes
────────────────────────────── 8  words found that the left  3  letters match the right letters which a word has a minimal length of  6

Ring 

load "stdlib.ring"

cStr = read("unixdict.txt")
wordList = str2list(cStr)
num = 0

see "working..." + nl
see "Words are:" + nl

ln = len(wordList)
for n = ln to 1 step -1
    if len(wordList[n]) < 6
       del(wordList,n)
    ok
next

for n = 1 to len(wordList)
    if left(wordList[n],3) = right(wordList[n],3) 
       num = num + 1
       see "" + num + ". " + wordList[n] + nl
    ok
next

see "done..." + nl

Output: 

working...
Words are:
1. antiperspirant
2. calendrical
3. einstein
4. hotshot
5. murmur
6. oshkosh
7. tartar
8. testes
done...

RPL

The only way to use unixdict.txt as input is to convert it into a list of 25104 strings. Luckily, emulators can handle such a big data structure in RAM.

Works with: Halcyon Calc version 4.2.7

≪ { } 

  1 UnixDict SIZE FOR j 
     ‘UnixDict’ j GET     
     IF DUP SIZE 5 ≤ THEN DROP ELSE 
        DUP 1 3 SUB 
        OVER DUP SIZE DUP 2 - SWAP SUB 
        IF == THEN + ELSE DROP END 
     END 
  NEXT
≫ ≫ ‘SAME3’ STO
Output:
1: { "antiperspirant" "calendrical" "einstein" "hotshot" "murmur" "oshkosh" "tartar" "testes" }

Ruby 

puts File.readlines("unixdict.txt", chomp: true).select{|w| w.end_with?(w[0,3]) && w.size > 5}
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Rust 

use std::fs;

fn firstsamelast(word: &&str, min_same: usize) -> bool {
    let n = word.len();
    return n >= 2 * min_same && word[..min_same] == word[n - min_same..];
}

fn main() {
    let wordsfile = fs::read_to_string("unixdict.txt").unwrap().to_lowercase();
    let words = wordsfile.split_whitespace().filter(|w| firstsamelast(w, 3));
    for (i, w) in words.enumerate() {
        print!("{:<16}{}", w, if (i + 1) % 4 == 0 { "\n" } else { "" });
    }
    return ();
}
Output:
antiperspirant  calendrical     einstein        hotshot
murmur          oshkosh         tartar          testes

sed 

/^\(...\).*\1$/!d
Output:
$ sed -f ends3eq.sed unixdict.txt
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Sidef 

File("unixdict.txt").open_r.each {|word|
    word.len > 5 || next
    if (word.ends_with(word.first(3))) {
        say word
    }
}
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Swift 

import Foundation

do {
    try String(contentsOfFile: "unixdict.txt", encoding: String.Encoding.ascii)
        .components(separatedBy: "\n")
        .filter{$0.count > 5 && $0.prefix(3) == $0.suffix(3)}
        .enumerated()
        .forEach{print("\($0.0 + 1). \($0.1)")}
} catch {
    print(error.localizedDescription)
}
Output:
1. antiperspirant
2. calendrical
3. einstein
4. hotshot
5. murmur
6. oshkosh
7. tartar
8. testes

VBScript

After building a program checking for the 3 letters in any order, I found people just checked the same trigraph at start and end. I modified my program so it puts an asterisk after the words in the "standard" answer. Run the ssript with CScript. 

with createobject("ADODB.Stream")
  .charset ="UTF-8"
  .open
  .loadfromfile("unixdict.txt")
  s=.readtext
end with  
a=split (s,vblf)

set d= createobject("Scripting.Dictionary")
for each aa in a
  x=trim(aa)
  l=len(x)
  if l>5 then
   d.removeall
   for i=1 to 3
     m=mid(x,i,1)
     if not d.exists(m) then d.add m,null
   next
   res=true
   for i=l-2 to l
     m=mid(x,i,1)
     if not d.exists(m) then 
       res=false:exit for 
      else
        d.remove(m)
      end if        
   next 
   if res then 
     wscript.stdout.write left(x & space(15),15)
     if left(x,3)=right(x,3) then  wscript.stdout.write "*"
     wscript.stdout.writeline
    end if 
  end if
next
Output:
alfalfa
antiperspirant *
calendrical    *
cataract
deadhead
earthenware
einstein       *
encumbrance
greenberg
hannah
hotshot        *
marjoram
murmur         *
oshkosh        *
tartar         *
teammate
tenement
testes         *

V (Vlang) 

import os

fn main() {
    mut result :=""
	unixdict := os.read_file("./unixdict.txt") or {println("Error: file not found") exit(1)}
	for word in unixdict.split_into_lines() {
		if word.len > 5 && word.substr(0, 3) == word.substr(word.len - 3, word.len) {
			result += word + "\n"
		}
	}
	println(result)
}
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes

Wren

Library: Wren-fmt
import "io" for File
import "./fmt" for Fmt

var wordList = "unixdict.txt" // local copy
var count = 0
File.read(wordList).trimEnd().split("\n").
    where { |w|
        return w.count > 5 && (w[0..2] == w[-3..-1])
    }.
    each { |w|
        count = count + 1
        Fmt.print("$d: $s", count, w)
    }
Output:
1: antiperspirant
2: calendrical
3: einstein
4: hotshot
5: murmur
6: oshkosh
7: tartar
8: testes

XPL0 

string 0;               \Use zero-terminated strings
int  I, Ch, Len;
char Word(100); \(longest word in unixdict.txt is 22 chars)
def  LF=$0A, CR=$0D, EOF=$1A;
[FSet(FOpen("unixdict.txt", 0), ^I);    \open dictionary and set it to device 3
OpenI(3);
repeat  I:= 0;
        loop    [repeat Ch:= ChIn(3) until Ch # CR;     \remove possible CR
                if Ch=LF or Ch=EOF then quit;
                Word(I):= Ch;
                I:= I+1;
                ];
        Word(I):= 0;                    \terminate string
        Len:= I;
        if Len >= 6 then
            if Word(0) = Word(Len-3) &
               Word(1) = Word(Len-2) &
               Word(2) = Word(Len-1) then
                  [Text(0, Word);  CrLf(0)];
until   Ch = EOF;
]
Output:
antiperspirant
calendrical
einstein
hotshot
murmur
oshkosh
tartar
testes
Retrieved from "https://rosettacode.org/wiki/Find_words_whose_first_and_last_three_letters_are_equal?oldid=374474"
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