Compilare: main.cpp: In function 'int main()': main.cpp:28:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(s.size()==n) ~~~~~~~~^~~ main.cpp:39:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(s.size()==n){ ~~~~~~~~^~~ main.cpp:10:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] { freopen("minmaxstore.in", "r",stdin); ^ main.cpp:11:44: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("minmaxstore.out", "w", stdout); ^ main.cpp:13:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ main.cpp:15:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:17:44: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &v[i].x, &v[i].y); ^ main.cpp:18:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &minn, &maxx); ^