#include <iostream> using namespace std; int main() { char s[20] = {'E', 'E', 'E', 'E', 'E', 'E', 'D', 'C', 'B', 'A', 'A'}; int n = 0; cin >> n; if(n < 0 || n > 100) cout << 'F' << endl; else cout << s[n / 10] << endl; ...