#include <bits/stdc++.h>
using namespace std;
const double PI = M_PI;
const int INF = -1 * 1e9;
const long long limit = 1 * 1e12;
const int MOD1 = 1e9 + 711;
const int MOD2 = 1e9 + 933;
const int MOD3 = 1e9 + 993;
const int maxn = 1e6 + 100;
int main() {
  cout.tie(0);
  cin.tie(0);
  ios_base::sync_with_stdio(0);
  int n;
  cin >> n;
  vector<int> a(n), b(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
    b[i] = a[i];
  }
  sort(b.begin(), b.end());
  int cnt = 0;
  for (int i = 0; i < n; ++i) {
    if (a[i] != b[i]) {
      ++cnt;
    }
  }
  if (cnt <= 2) {
    cout << "YES";
  } else {
    cout << "NO";
  }
  cerr << "\n\nTime elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.\n";
  return 0;
}
