Compilare: user.cpp: In function ‘void dijkstra(int)’: user.cpp:42:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < G[k].size(); i++) ~~^~~~~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:70:19: warning: unused variable ‘y’ [-Wunused-variable] int x,y,c; ^ user.cpp:70:21: warning: unused variable ‘c’ [-Wunused-variable] int x,y,c; ^