Aha! Algorithms (Column 2 of Programming Pearls)

1 /* Copyright (C) 1999 Lucent Technologies */
2 /* From 'Programming Pearls' by Jon Bentley */
3
4 /* sign.c -- sign each line of a file for finding anagrams
5 The input line "stop" gives the output line "opst stop"
6 */
7
8 #include <stdio.h>
9 #include <stdlib.h>
#include <string.h>
#define WORDMAX 100

int charcomp(char *x, char *y)
{ return *x - *y;
}

int main()
{ char word[WORDMAX], sig[WORDMAX];
while (scanf("%s", word) != EOF) {
strcpy(sig, word);
qsort(sig, strlen(sig), sizeof(char), charcomp);
printf("%s %s\n", sig, word);
}
return 0;
}