Compilare: main.c: In function 'citire': main.c:7:2: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("dfs.in", "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:8:2: warning: ignoring return value of 'freopen', declared with attribute warn_unused_result [-Wunused-result] freopen("dfs.out", "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:9:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^~~~~~~~~~~~~~~~~~~~~~ main.c:13:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^~~~~~~~~~~~~~~~~~~~~~