Compilare: user.c: In function ‘main’: user.c:28:5: warning: implicit declaration of function ‘qsort’ [-Wimplicit-function-declaration] qsort(&x[1], n, sizeof(int), cmp); ^ user.c:78:5: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘long long int’ [-Wformat=] fprintf(out, "%d\n", a[1][n]); ^ user.c:22:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d\n", &n); ^ user.c:25:15: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", x+i); ^