You are given a string consisting only of the characters and .
You must insert exactly one character and exactly one character into the string. Each character may be inserted at any position, including the beginning or the end of the string. The order of the original characters must not be changed.
Determine whether these insertions can produce a string in which any two adjacent characters are different.
The first line contains an integer (1 \leq n \leq 10^5) — the length of the string.
The second line contains a string of length , consisting only of the characters and .
Print YES if it is possible to obtain the required string, or NO otherwise.
Example 1
Example 2
Example 3
In the first example, you can insert between the two original zeros and between the two original ones. The resulting string is 010101.
In the second example, after the insertions, the string will contain four zeros and two ones, so it is impossible to obtain the required string.
In the third example, you can append and then to the end of the string. The resulting string is 0101010.
points — n \leq 100.
points — n \leq 2000.
points — no additional constraints.