#include<iostream>
using namespace std;
int main(){
  int N;
  cin >> N;
  int k=0;
  for(int i=0; i<N; i++){
    int p;
    cin >> p;
    if(p != i+1) k++;
  }
  if(k<=2) cout << "YES" << endl;
  else cout << "NO" << endl;
  return 0;
}
### Prompt

Create a solution in CPP for the following problem:

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

### Response

```cpp
#include<iostream>
using namespace std;
int main(){
  int N;
  cin >> N;
  int k=0;
  for(int i=0; i<N; i++){
    int p;
    cin >> p;
    if(p != i+1) k++;
  }
  if(k<=2) cout << "YES" << endl;
  else cout << "NO" << endl;
  return 0;
}
```