Compilare: main.cpp: In function 'std::pair<int, int> dfs(int, int, int)': main.cpp:25:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<adj[cr].size();i++){ ~^~~~~~~~~~~~~~~ main.cpp:33:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<adj[cr].size();i++){ ~^~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:55:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("tree7.in","r",stdin); ^ main.cpp:56:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("arbore7.out","w",stdout); ^