We have a sequence p = {p_1,\ p_2,\ ...,\ p_N} which is a permutation of {1,\ 2,\ ...,\ N}.
You can perform the following operation at most once: choose integers i and $j (1 \leq i < j \leq N)$, and swap p_i and p_j. Note that you can also choose not to perform it.
Print YES if you can sort p in ascending order in this way, and NO otherwise.

-----Constraints-----
- All values in input are integers.
- $2 \leq N \leq 50$
- p is a permutation of {1,\ 2,\ ...,\ N}.

-----Input-----
Input is given from Standard Input in the following format:
N
p_1 p_2 ... p_N

-----Output-----
Print YES if you can sort p in ascending order in the way stated in the problem statement, and NO otherwise.

-----Sample Input-----
5
5 2 3 4 1

-----Sample Output-----
YES

You can sort p in ascending order by swapping p_1 and p_5.

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