Compilare: main.c: In function 'main': main.c:60:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in", "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:61:5: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out", "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:63:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^~~~~~~~~~~~~~~~~~~~~~ main.c:66:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &u, &v, &w); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~