Compilare: user.cpp: In function ‘int main()’: user.cpp:12:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("poligon7.in","r",stdin); ^ user.cpp:13:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("poligon7.out","w",stdout); ^ user.cpp:15:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&p,&t); ^ user.cpp:18:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:19:69: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1;i<=n;i++) scanf("%d%d",&v[i].first,&v[i].second); ^ user.cpp:32:109: warning: ‘vec’ may be used uninitialized in this function [-Wmaybe-uninitialized] dist[j]=min(dist[j],1LL*(v[nod].first-v[j].first)*(v[nod].first-v[j].first)+1LL*(v[nod].second-v[j].second)*(v[nod].second-v[j].second)); ~~~~~~~^~~~~~