Compilare: user.c: In function ‘main’: user.c:61:10: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("easygraph.out", "w", stdout); ^ user.c:63:14: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] for (fscanf(f, "%d", &T); T; T--) { ^ user.c:65:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &N, &M); ^ user.c:67:13: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%lld", &val[u]); ^ user.c:71:13: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &u, &v); ^