Compilare: main.cpp: In function 'int dfs(const graph&, int, int)': main.cpp:72:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < graph.nodes.size(); i++) ~~^~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'long long int bfs(const graph&)': main.cpp:91:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < graph.nodes.size(); i++) ~~^~~~~~~~~~~~~~~~~~~~ main.cpp:93:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < graph.nodes.size(); j++) ~~^~~~~~~~~~~~~~~~~~~~