Compilare: user.c:46:6: warning: conflicting types for built-in function ‘pow’ [enabled by default] void pow(int *A, int *B, int *C, int n) { ^ user.c: In function ‘mul’: user.c:33:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘cpy’: user.c:43:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.c: In function ‘main’: user.c:65:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("smexp.in", "r", stdin); ^ user.c:66:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("smexp.out", "w", stdout); ^ user.c:69:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i", &n, &k); ^ user.c:75:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &A[id(i, j)]); ^