Hailstone sequence: Difference between revisions
→{{header|ARM Assembly}}
No edit summary |
Puppydrum64 (talk | contribs) |
||
Line 847:
{{output}}
<pre>{|number(s) giving longest sequence length|:{77031}, |length of sequence|:351}</pre>
=={{header|ARM Assembly}}==
Output is in hexadecimal but is otherwise correct. Only Parts 1 and 2 are included for now.
Because of the Game Boy Advance's limited screen size, only the first 4 and last 4 entries are printed to the screen. The emulator's memory dump can show the rest.
<lang ARM Assembly> .org 0x08000000
b ProgramStart
;cartridge header goes here
;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Program Start
.equ ramarea, 0x02000000
.equ CursorX,ramarea
.equ CursorY,ramarea+1
.equ hailstoneram,0x02000004
ProgramStart:
mov sp,#0x03000000 ;Init Stack Pointer
mov r4,#0x04000000 ;DISPCNT - LCD Video Controller
mov r2,#0x403 ;4= Layer 2 on / 3= ScreenMode 3
str r2,[r4] ;now the user can see the screen
bl ResetTextCursors ;set text cursors to top left of screen. This routine, as well as the other I/O
; routines, were omitted to keep this entry short.
mov r0,#27
adr r1,HailStoneMessage_Init
bl PrintString
bl NewLine
bl ShowHex32
bl NewLine
bl NewLine
bl Hailstone
;function is complete, return the output
adr r1,HailStoneMessage_0
bl PrintString
bl NewLine
ldr r1,HailStoneRam_Mirror ;mov r2,0x02000004
ldr r0,[r1],#4
bl ShowHex32
bl NewLine
ldr r0,[r1],#4
bl ShowHex32
bl NewLine
ldr r0,[r1],#4
bl ShowHex32
bl NewLine
ldr r0,[r1],#4
bl ShowHex32
bl NewLine
bl NewLine
adr r1,HailStoneMessage_1
bl PrintString
bl NewLine
ldr r0,[r2],#4
bl ShowHex32
bl NewLine
ldr r0,[r2],#4
bl ShowHex32
bl NewLine
ldr r0,[r2],#4
bl ShowHex32
bl NewLine
ldr r0,[r2],#4
bl ShowHex32
bl NewLine
bl NewLine
adr r1,HailStoneMessage_2
bl PrintString
bl NewLine
mov r0,r3
bl ShowHex32
forever:
b forever ;we're done, so trap the program counter.
Hailstone:
;input: R0 = n.
;out: r2 = pointer to last 4 entries
; r3 = length of sequence
;reg usage:
;R1 = scratchpad
;R3 = counter for entries in the sequence.
;R4 = pointer to output ram
stmfd sp!,{r4-r12,lr}
mov r5,#0x02000000
add r5,r5,#4
str r0,[r5],#4 ;store in hailstone ram and post-inc by 4
mov r3,#0
loop_hailstone:
add r3,r3,#1 ;represents number of entries in the sequence
cmp r0,#1
beq hailstone_end
tst r0,#1
;;;; executes only if r0 was even
moveq r0,r0,lsr #1 ;divide
;;;; executes only if r0 was odd
movne r1,r0
movne r0,r0,lsl #1
addne r0,r1,r0
addne r0,r0,#1
str r0,[r5],#4 ;store in hailstone ram, post inc by 4
b loop_hailstone
hailstone_end:
sub r5,r5,#16 ;subtract 16 to get pointer to last 4 entries.
mov r2,r5 ;output ptr to last 4 entries to r2.
;pointer to first 4 entries is 0x02000004
ldmfd sp!,{r4-r12,pc}
HailStoneRam_Mirror:
.long 0x02000004
HailstoneMessage_Init:
.byte "Your input was:",255
.align 4
HailstoneMessage_0:
.byte "First 4 numbers are:",255
.align 4
HailstoneMessage_1:
.byte "Last 4 numbers are:",255
.align 4
HailstoneMessage_2:
.byte "Sequence length is:",255
.align 4
;;;;;;;;;;; EVERYTHING PAST THIS POINT IS JUST I/O ROUTINES FOR PRINTING NUMBERS AND WORDS TO THE GAME BOY ADVANCE'S SCREEN
;;;;;;;;;;; I ASSURE YOU THAT ALL OF IT WORKS BUT CHANCES ARE YOU DIDN'T COME HERE TO SEE THAT.
;;;;;;;;;;; THANKS TO KEITH OF CHIBIAKUMAS.COM FOR WRITING THEM!</lang>
{{out}}
<pre>
Your input was:
0000001B
First 4 numbers are:
0000001B
00000052
00000029
0000007C
Last 4 numbers are:
00000008
00000004
00000002
00000001
Sequence length is:
00000070
</pre>
[https://ibb.co/WzgWjZ9 Picture of output on VisualBoyAdvance screen]
=={{header|Arturo}}==
| |||