source_code: import java.util.List;
  import java.io.InputStreamReader;
  import java.io.IOException;
  import java.util.Arrays;
  import java.util.InputMismatchException;
  import java.io.BufferedReader;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.util.Random;
  import java.io.Reader;
  import java.io.Writer;
  import java.io.InputStream;
  
  /**
   * Built using CHelper plug-in
   * Actual solution is at the top
   * @author niyaznigmatul 
   */
  public class Main {
  	public static void main(String[] args) {
  		InputStream inputStream = System.in;
  		OutputStream outputStream = System.out;
  		FastScanner in = new FastScanner(inputStream);
  		FastPrinter out = new FastPrinter(outputStream);
  		TaskA solver = new TaskA();
  		solver.solve(1, in, out);
  		out.close();
  	}
  }
  
  class TaskA {
  	public void solve(int testNumber, FastScanner in, FastPrinter out) {
          int n = in.nextInt();
          int[] a = new int[n];
          for (int i = 0; i < n; i++) {
              a[i] = in.nextInt();
          }
          int[] b = a.clone();
          ArrayUtils.sort(b);
          int count = 0;
          for (int i = 0; i < n; i++) {
              if (a[i] != b[i]) {
                  ++count;
              }
          }
          out.println(count <= 2 ? "YES" : "NO");
  	}
  }
  
  class FastScanner extends BufferedReader {
  
      boolean isEOF;
  
      public FastScanner(InputStream is) {
          super(new InputStreamReader(is));
      }
  
      public int read() {
          try {
              int ret = super.read();
              if (isEOF && ret < 0) {
                  throw new InputMismatchException();
              }
              isEOF = ret == -1;
              return ret;
          } catch (IOException e) {
              throw new InputMismatchException();
          }
      }
  
      static boolean isWhiteSpace(int c) {
          return c >= -1 && c <= 32;
      }
  
      public int nextInt() {
          int c = read();
          while (isWhiteSpace(c)) {
              c = read();
          }
          int sgn = 1;
          if (c == '-') {
              sgn = -1;
              c = read();
          }
          int ret = 0;
          while (!isWhiteSpace(c)) {
              if (c < '0' || c > '9') {
                  throw new NumberFormatException("digit expected " + (char) c
                          + " found");
              }
              ret = ret * 10 + c - '0';
              c = read();
          }
          return ret * sgn;
      }
  
      }
  
  class FastPrinter extends PrintWriter {
  
      public FastPrinter(OutputStream out) {
          super(out);
      }
  
      public FastPrinter(Writer out) {
          super(out);
      }
  
  
  }
  
  class ArrayUtils {
  
      public static void sort(int[] a) {
          Random rand = new Random(System.nanoTime());
          for (int i = 0; i < a.length; i++) {
              int j = rand.nextInt(i + 1);
              int t = a[i];
              a[i] = a[j];
              a[j] = t;
          }
          Arrays.sort(a);
      }
  
  
      }
  
  