python1加到n

while True:
    a = 0
    n = input('从0开始加到您所输入的数字：')
    if n.isdigit() == True:
        n = int(n)
        for i in range(n+1):
            a += i
        else:
            print('计算完成，结果为', a)
        s = input('输入q退出或者任意字符继续 : ')
        if s == 'q':
            break
    else:
        print('请输入正整数！')
print('程序结束！')