Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:28:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[x].v.size(); i++) ^ user.cpp: In function ‘void idfs(int)’: user.cpp:39:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[x].iv.size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:77:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<a[i].size(); j++) ^