Letter frequency: Difference between revisions

=={{header|Cowgol}}==

<lang cowgol>include "cowgol.coh";

include "argv.coh";

include "file.coh";

# Get filename from command line

ArgvInit();

var file := ArgvNext();

if file == (0 as [uint8]) then

print("error: no file name\n");

ExitWithError();

end if;

# Open the file

var fcb: FCB;

if FCBOpenIn(&fcb, file) != 0 then

print("error: cannot open file\n");

ExitWithError();

end if;

# Counters for each letter

var letterCount: uint32[26];

MemZero(&letterCount as [uint8], @bytesof letterCount);

# Count every letter

var len := FCBExt(&fcb);

while len != 0 loop

len := len - 1;

var ch := (FCBGetChar(&fcb) | 32) - 'a';

if ch >= @sizeof letterCount then

continue;

end if;

letterCount[ch] := letterCount[ch] + 1;

end loop;

# Close the file

var foo := FCBClose(&fcb);

# Print value for each letter

ch := 0;

while ch < @sizeof letterCount loop

print_char(ch + 'A');

print(": ");

print_i32(letterCount[ch]);

print_nl();

ch := ch + 1;

end loop;</lang>

{{out}}

The result of running the program on its own source file:

<pre>A: 22

B: 11

C: 46

D: 9

E: 80

F: 32

G: 6

H: 26

I: 42

J: 0

K: 0

L: 39

M: 7

N: 53

O: 45

P: 14

Q: 0

R: 47

S: 8

T: 59

U: 18

V: 11

W: 5

X: 4

Y: 2

Z: 3</pre>