Compilare: main.cpp: In function 'void solve()': main.cpp:75:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < e.size(); ++i) { ~~^~~~~~~~~~ main.cpp:34:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %lld", &n, &m); ^ main.cpp: In function 'int main()': main.cpp:81:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("galeti2.in", "r", stdin); ^ main.cpp:82:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("galeti2.out", "w", stdout); ^