#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int arr[n];
  for (int i = 0; i < n; i++) {
    cin >> arr[i];
  }
  int cp_arr[n];
  copy(arr, arr + n, cp_arr);
  sort(arr, arr + n);
  int ct = 0;
  for (int i = 0; i < n; i++) {
    if (cp_arr[i] != arr[i]) ct++;
  }
  if (ct <= 2)
    cout << "YES";
  else
    cout << "NO";
}
