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Can someone tell me what's wrong with my solution? Thanks in advance.


/* acm.uva.es */

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

int N, length, was[21], array[21], list[21][21], poss[21], cnt;
unsigned long sol;

int cmp (const void *a, const void *b) {
if (* (const int *) a > * (const int *) b ...