Compilare: user.cpp: In function ‘void solve()’: user.cpp:49:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<G[x].size();i++){ ^ user.cpp: In function ‘void read()’: user.cpp:28:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:32:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&c); ^