题解 | #[NOIP2010]数字统计#
[NOIP2010]数字统计
http://www.nowcoder.com/practice/179d9754eeaf48a1b9a49dc1d438525a
def compute_num(x, y): count = 0 for i in range(x, y + 1): count += str(i).count('2') return count
a, b = map(int, input().split()) print(compute_num(a, b))