source_code: 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());
  	}
  }