/*******************************************
作者：    gnehoaix
功能：    输入成绩并转换为：A+ A B C D E 等级(使用if-else)
时间：    2019\4\24
********************************************/
# include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
using namespace std;
int main()
{
	const vector<string> grade = { "E","D","C","B","A","A+" };
	vector<string> lettergrade;
	unsigned  input;
	while (cin >> input && input >= 0)
	{
		if (input >= 60)
		{
			lettergrade.push_back( grade[(input - 50) / 10]);
		}
		else
			lettergrade.push_back(grade[0]);
	}
	for (auto i : lettergrade)
		cout << i << endl;	
	
	return 0;
}

/*******************************************
作者：    gnehoaix
功能：    输入成绩并转换为：A+ A B C D E 等级(使用?:)
时间：    2019\4\24
********************************************/
# include "stdafx.h"
#include <iostream>
#include <string>
#include <vector>
using namespace std;
int main()
{
	const vector<string> grade = {"E","D","C","B","A","A+" };
	vector<string> lettergrade;
	unsigned  input;

	while (cin >> input && input >= 0)	
		// 使用条件语句，当60时，代表grade[1],此类推
			input >= 60 ? lettergrade.push_back( grade[(input - 50) / 10]) : lettergrade.push_back(grade[0]); 

	for (auto i : lettergrade)
		cout << i << endl;		
	
	return 0;