Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:31:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<a[x].size();i++) ^ user.cpp: In function ‘void dfs1(int)’: user.cpp:40:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<b[x].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:72:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<c[d[i].p].size();j++) ^