Compilare: user.cpp: In function ‘bool bfs()’: user.cpp:23:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<ad[start].size();i++) ~^~~~~~~~~~~~~~~~~ user.cpp: In function ‘bool flux()’: user.cpp:47:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<ad[i].size();j++) ~^~~~~~~~~~~~~ user.cpp: In function ‘void dfs(int)’: user.cpp:64:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[x].size();i++) ~^~~~~~~~~~~~ user.cpp:71:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<v[x].size();i++) ~^~~~~~~~~~~~