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
N = int(raw_input())
A = map(int, raw_input().split())

def solve(N, A):
    problems = []
    for i, x in enumerate(A):
        if x != i+1:
            problems.append(i)
    if len(problems) < 2: return True
    if len(problems) > 2: return False
    i0, j0 = problems
    A[i0], A[j0] = A[j0], A[i0]
    return all(A[k] < A[k+1] for k in xrange(N-1))

print "YES" if solve(N, A) else "NO"
