Compilare: user.cpp: In function ‘void dfs1(int, int)’: user.cpp:34:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0 ; i < a[x].size() ; i ++ ) ~~^~~~~~~~~~~~~ user.cpp: In function ‘void dfs2(int, int)’: user.cpp:51:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0 ; i < a[x].size() ; i ++ ) ~~^~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:80:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0 ; i < rez.size() ; i++) ~~^~~~~~~~~~~~