Compilare: main.cpp: In function 'void dfs(int, int)': main.cpp:15:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<g[a].size();i++) ~^~~~~~~~~~~~ main.cpp:18:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<g[b].size();j++) ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:44:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<g[i].size();j++){ ~^~~~~~~~~~~~