Compilare: user.cpp: In function ‘int main()’: user.cpp:120:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(poz + (1 << i) <= a[b].size() && verif(a[b][poz + (1 << i) - 1])) ^ user.cpp:62:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("poligon.in","r",stdin); ^ user.cpp: In function ‘int ianr()’: user.cpp:47:46: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf , D , 1 , stdin) , ppoz = 0; ^ user.cpp:54:50: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buf , D , 1 , stdin) , ppoz = 0; ^