#P1660. 数位平方和

数位平方和

Description

Define S(n)S(n) as the sum of the kk-th powers of the digits of nn.

Define H(n)H(n) as the maximum value satisfying H(n)min{n,H(S(n))}H(n) \le \min\{n, H(S(n))\}.

Compute i=ABH(i)mod(107+7)\sum_{i=A}^{B} H(i) \bmod (10^7 + 7).

Input Format

One line with three integers k,A,Bk, A, B.

Output Format

One integer, equal to i=ABH(i)mod(107+7)\sum_{i=A}^{B} H(i) \bmod (10^7 + 7).

2 1 5
14

Hint

For 20%20\% of the testdata, A,B50A, B \le 50. For 100%100\% of the testdata, 1A,B1061 \le A, B \le {10}^6, 1k61 \le k \le 6.

Translated by ChatGPT 5