Compilare: user.cpp: In function ‘void df(int)’: user.cpp:15:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < L[x].size(); i ++) { ^ user.cpp: In function ‘void dfT(int)’: user.cpp:23:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < G[x].size(); i ++) { ^ user.cpp: In function ‘int main()’: user.cpp:60:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < s[i].size(); j ++) ^