当前没有测试数据。

E - Swap

Score : $500$ points

Problem Statement

Given is a string $S$ consisting of K, E, Y.

How many strings are there that can be obtained with at most $K$ swaps of two adjacent characters in $S$?

Constraints

• $2 \leq |S| \leq 30$
• $0 \leq K \leq 10^9$
• $S$ consists of K, E, Y.

Input

Input is given from Standard Input in the following format:

$S$

$K$

Output

Print the answer.

KEY
1

3

With at most one swap, there are three strings that can be obtained: KEY, EKY, KYE.

KKEE
2

4

With at most two swaps, there are four strings that can be obtained: KKEE, KEKE, EKKE, KEEK.

KKEEYY
1000000000

90