Compilare: user.cpp: In function ‘int main()’: user.cpp:50:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i<lns.size(); ++i){ ^ user.cpp:27:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("flori2.in","r",stdin); ^ user.cpp:28:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("flori2.out","w",stdout); ^ user.cpp:30:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ user.cpp:35:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:38:42: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] pts.push_back(make_pair(x,y)); ^