import java.io.*;
import java.util.*;
import java.math.*;

public class A {
    static BufferedReader in;
    static PrintWriter out;
    static StringTokenizer st;
    static Random rnd;

    void solve() throws IOException {
        int n = nextInt();

        int[] arr = new int[n];
        Integer[] arrCopy = new Integer[n];

        for (int i = 0; i < n; i++)
            arr[i] = arrCopy[i] = nextInt();

        Arrays.sort(arrCopy);

        int bad = 0;

        for (int i = 0; i < n; i++)
            if (arr[i] != arrCopy[i])
                ++bad;

        boolean fail = bad > 2;

        out.println(!fail ? "YES" : "NO");
    }

    public static void main(String[] args) {
        new A().run();
    }

    public void run() {
        try {
            in = new BufferedReader(new InputStreamReader(System.in));
            out = new PrintWriter(System.out);

            rnd = new Random();

            solve();

            out.close();
        } catch (IOException e) {
            e.printStackTrace();
            System.exit(42);
        }
    }

    String nextToken() throws IOException {
        while (st == null || !st.hasMoreTokens()) {
            String line = in.readLine();

            if (line == null)
                return null;

            st = new StringTokenizer(line);
        }

        return st.nextToken();
    }

    int nextInt() throws IOException {
        return Integer.parseInt(nextToken());
    }

    long nextLong() throws IOException {
        return Long.parseLong(nextToken());
    }

    double nextDouble() throws IOException {
        return Double.parseDouble(nextToken());
    }
}