#include<cstdio> #include<iostream> using namespace std; int main() { int score; while (cin >> score) { if (score > 100 || score < 0) { printf("Score is error!\n"); } else if (score >= 90) { printf("A\n"); } else if (score >= 80) { printf("B\n"); } else if (score >= 70) { printf("C\n"); } else if (score >= 60) { printf("D\n"); } else { printf("E\n"); } } return 0; }