Compilare: user.cpp: In function ‘bool cmp(interv, interv)’: user.cpp:11:16: warning: suggest parentheses around assignment used as truth value [-Wparentheses] if (a.d = b.d ) if (a.s < b.s) return 1; ^ user.cpp:11:5: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (a.d = b.d ) if (a.s < b.s) return 1; ^ user.cpp:14:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:16:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("int.in", "r", stdin); ^ user.cpp:17:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("int.out", "w", stdout); ^ user.cpp:18:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:19:60: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i = 1; i <= n; i++) scanf("%d%d", &a[i].s, &a[i].d); ^