source_code: import java.io.OutputStreamWriter;
  import java.io.BufferedWriter;
  import java.util.Locale;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.util.RandomAccess;
  import java.util.AbstractList;
  import java.io.Writer;
  import java.util.List;
  import java.io.IOException;
  import java.math.BigDecimal;
  import java.util.Arrays;
  import java.util.InputMismatchException;
  import java.math.BigInteger;
  import java.util.Collections;
  import java.io.InputStream;
  
  /**
   * Built using CHelper plug-in
   * Actual solution is at the top
   * @author Jacob Jiang
   */
  public class Main {
  	public static void main(String[] args) {
  		InputStream inputStream = System.in;
  		OutputStream outputStream = System.out;
  		InputReader in = new InputReader(inputStream);
  		OutputWriter out = new OutputWriter(outputStream);
  		TaskA solver = new TaskA();
  		solver.solve(1, in, out);
  		out.close();
  	}
  }
  
  class TaskA {
  	public void solve(int testNumber, InputReader in, OutputWriter out) {
          int n = in.nextInt();
          int[] a = in.nextIntArray(n);
          int[] b = a.clone();
          ArrayUtils.safeSort(b);
          int diff = 0;
          for (int i = 0; i < n; i++) {
              if (a[i] != b[i])
                  diff++;
          }
          out.println(diff <= 2 ? "YES" : "NO");
      }
  }
  
  class InputReader {
  
      private InputStream stream;
      private byte[] buf = new byte[1 << 16];
      private int curChar;
      private int numChars;
  
      public InputReader(InputStream stream) {
          this.stream = stream;
      }
  
      public int read() {
          if (numChars == -1)
              throw new InputMismatchException();
          if (curChar >= numChars) {
              curChar = 0;
              try {
                  numChars = stream.read(buf);
              } catch (IOException e) {
                  throw new InputMismatchException();
              }
              if (numChars <= 0)
                  return -1;
          }
          return buf[curChar++];
      }
  
      public int nextInt() {
          int c = read();
          while (isSpaceChar(c))
              c = read();
          int sgn = 1;
          if (c == '-') {
              sgn = -1;
              c = read();
          }
          int res = 0;
          do {
              if (c < '0' || c > '9')
                  throw new InputMismatchException();
              res *= 10;
              res += c & 15;
              c = read();
          } while (!isSpaceChar(c));
          return res * sgn;
      }
  
      public static boolean isSpaceChar(int c) {
          return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
      }
  
      public int[] nextIntArray(int count) {
          int[] result = new int[count];
          for (int i = 0; i < count; i++) {
              result[i] = nextInt();
          }
          return result;
      }
  
      }
  
  class OutputWriter {
      private PrintWriter writer;
  
      public OutputWriter(OutputStream stream) {
          writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(stream)));
      }
  
      public OutputWriter(Writer writer) {
          this.writer = new PrintWriter(writer);
      }
  
      public void println(String x) {
          writer.println(x);
      }
  
      public void close() {
          writer.close();
      }
  
      }
  
  class ArrayUtils {
  
  
  
      public static List<Integer> asList(int[] array) {
          return new IntList(array);
      }
  
      private static class IntList extends AbstractList<Integer> implements RandomAccess {
  
          int[] array;
  
          private IntList(int[] array) {
              this.array = array;
          }
  
          public Integer get(int index) {
              return array[index];
          }
  
          public Integer set(int index, Integer element) {
              int result = array[index];
              array[index] = element;
              return result;
          }
  
          public int size() {
              return array.length;
          }
      }
  
      public static void safeSort(int[] array) {
          Collections.shuffle(asList(array));
          Arrays.sort(array);
      }
  
      }
  
  