Compilare: main.cpp: In function 'int main()': main.cpp:27:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<v.size();++i) ~^~~~~~~~~ main.cpp:18:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("aria.in","r",stdin); ^ main.cpp:19:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("aria.out","w",stdout); ^ main.cpp:20:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ main.cpp:23:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%lf %lf",&x,&y); ^