Compilare: user.c: In function ‘main’: user.c:8:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("stramosi.in", "r", stdin); ^ user.c:9:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("stramosi.out", "w", stdout); ^ user.c:10:7: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &N, &M); ^ user.c:12:8: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &matrice[0][i+1]); ^ user.c:17:8: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &P[i], &Q[i]); ^