Giải bài trực tuyến

Given two strings s1 and s2. We can merge characters of two strings (with order in original strings) to get a new string.

For example : s1 = 'ab' and s2 = 'ba'.

We can merge to get st = 'abba' but not st = 'aabb'.

The Problem : Given two string contain only lowercase letters, count the number of palindrome by merging in different ways. 

Example: 'aba', 'abba' are palindrome, 'abc' and 'abca' aren't.

Input

- Two lines, each line contains a string, string's length isn't over 500.

Output

- A single integer is the number of palindrome after modulo 3210121.

Example

Input:
ab
ba

Output:
4