#P4701. Mike and Fax

Mike and Fax

Mike and Fax

题面翻译

给定一个字符串和一个整数 kk,问是不是恰好存在 kk 个子字符串是回文串,并且所有子字符串的长度一样长。

题目描述

While Mike was walking in the subway, all the stuff in his back-bag dropped on the ground. There were several fax messages among them. He concatenated these strings in some order and now he has string s s .

He is not sure if this is his own back-bag or someone else's. He remembered that there were exactly k k messages in his own bag, each was a palindrome string and all those strings had the same length.

He asked you to help him and tell him if he has worn his own back-bag. Check if the given string s s is a concatenation of k k palindromes of the same length.

输入格式

The first line of input contains string s s containing lowercase English letters ( 1<=s<=1000 1<=|s|<=1000 ).

The second line contains integer k k ( 1<=k<=1000 1<=k<=1000 ).

输出格式

Print "YES"(without quotes) if he has worn his own back-bag or "NO"(without quotes) otherwise.

样例 #1

样例输入 #1

saba
2

样例输出 #1

NO

样例 #2

样例输入 #2

saddastavvat
2

样例输出 #2

YES

提示

Palindrome is a string reading the same forward and backward.

In the second sample, the faxes in his back-bag can be "saddas" and "tavvat".