Compilare: main.cpp: In function 'void euler(std::pair<int, int>)': main.cpp:56:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i<graf[start.first][start.second].size(); i++) ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:74:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j<graf[graf[start.first][start.second][i].first][graf[start.first][start.second][i].second].size(); j++) ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'std::pair<std::pair<int, int>, int> bfs()': main.cpp:110:1: warning: control reaches end of non-void function [-Wreturn-type] } ^