Compilare: main.c: In function 'main': main.c:8:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen ("scara3.in", "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:9:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen ("scara3.out", "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:12:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &n); ^~~~~~~~~~~~~~~~ main.c:13:10: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] for (scanf ("%d", &i); i; i--) { ^~~~~~~~~~~~~~~~ main.c:14:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &a, &b); ^~~~~~~~~~~~~~~~~~~~~~ main.c:17:10: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] for (scanf ("%d", &i); i; i--) { ^~~~~~~~~~~~~~~~ main.c:18:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &a, &b); ^~~~~~~~~~~~~~~~~~~~~~