Compilare: user.cpp: In function ‘int main()’: user.cpp:43:74: warning: narrowing conversion of ‘coord.std::vector<_Tp, _Alloc>::operator[]<std::pair<int, int>, std::allocator<std::pair<int, int> > >(((std::vector<std::pair<int, int> >::size_type)i)).std::pair<int, int>::second’ from ‘int’ to ‘char’ inside { } [-Wnarrowing] v.push_back({coord[i].first, coord[j - 1].first, coord[i].second}); ^ user.cpp:30:31: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d %d " ,&c,&n); ^ user.cpp:32:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d %d " ,&l,&c); ^ user.cpp:47:25: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d " ,&m); ^ user.cpp:51:51: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d %d %d %d " ,&l1,&c1,&l2,&c2); ^