#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x;
  int a[100000 + 3], b[100000 + 3];
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    b[i] = a[i];
  }
  sort(b, b + n);
  int cnt = 1;
  for (int i = 0; i < n; i++) {
    if (a[i] != b[i]) {
      cnt++;
    }
  }
  if (cnt == 3 || cnt == 1) {
    cout << "YES";
    return 0;
  }
  cout << "NO";
  return 0;
}
