Compilare: main.cpp: In function 'void dfs1(int, int)': main.cpp:31:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<vec[x].size(); i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void dfs2(int, int, int)': main.cpp:55:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<vec[x].size(); i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:76:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<vec[1].size(); i++) ~^~~~~~~~~~~~~~