Compilare: main.cpp: In function 'void dfs(int, int)': main.cpp:15:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<L[nod].size();i++){ ~^~~~~~~~~~~~~~ main.cpp:30:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<L[nod].size();i++){ ~^~~~~~~~~~~~~~ main.cpp:40:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<L[nod].size();i++){ ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:100:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<3*chains[i].size();j++) ~^~~~~~~~~~~~~~~~~~~