Contest1414/E.py

while True:
    a=int(input())
    if a<0 or a>100:
        print('Score is error!')
    elif a<60:
        print('E')
    elif a<70:
        print('D')
    elif a<80:
        print('C')
    elif a<90:
        print('B')
    else:
        print('A')