p02958 AtCoder Beginner Contest 135 - 0 or 1 Swap
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.

Examples

Input

5
5 2 3 4 1


Output

YES


Input

5
2 4 3 5 1


Output

NO


Input

7
1 2 3 4 5 6 7


Output

YES
```python
N=int(input())
p=list(map(int,input().split()))
a=0
for i in range(N):
    if p[i]!=i+1:
        a+=1
if a>=3:
    print('NO')
else:
    print('YES')
```