Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:49:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(nx < 0 || ny < 0 || nx > x.size() || ny > y.size()) ^ user.cpp:49:59: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(nx < 0 || ny < 0 || nx > x.size() || ny > y.size()) ^ user.cpp: In function ‘void Solve()’: user.cpp:66:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i <= x.size(); ++i) ^ user.cpp:67:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j <= y.size(); ++j) ^ user.cpp: In function ‘void Read()’: user.cpp:14:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &rectangles, &N, &M); ^ user.cpp:18:112: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &vec[i].first.first, &vec[i].first.second, &vec[i].second.first, &vec[i].second.second); ^ user.cpp: In function ‘int main()’: user.cpp:74:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("colaj.in", "r", stdin); ^ user.cpp:75:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("colaj.out", "w", stdout); ^