Compilare: user.cpp: In function ‘int dijkstra()’: user.cpp:58:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<L[x].size();i++) { ^ user.cpp: In function ‘int main()’: user.cpp:119:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<L[x].size();i++) ^