source_code: import java.io.OutputStreamWriter;
  import java.io.BufferedWriter;
  import java.util.Comparator;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.io.Writer;
  import java.io.IOException;
  import java.util.Arrays;
  import java.util.InputMismatchException;
  import java.math.BigInteger;
  import java.io.InputStream;
  
  /**
   * Built using CHelper plug-in
   * Actual solution is at the top
   * @author Egor Kulikov (egor@egork.net)
   */
  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 count = in.readInt();
          int[] array = IOUtils.readIntArray(in, count);
          int[] sorted = array.clone();
          ArrayUtils.sort(sorted, IntComparator.DEFAULT);
          int differs = 0;
          for (int i = 0; i < count; i++) {
              if (array[i] != sorted[i])
                  differs++;
          }
          if (differs <= 2)
              out.printLine("YES");
          else
              out.printLine("NO");
      }
  }
  
  class InputReader {
  
      private InputStream stream;
      private byte[] buf = new byte[1024];
      private int curChar;
      private int numChars;
      private SpaceCharFilter filter;
  
      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 readInt() {
          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 - '0';
              c = read();
          } while (!isSpaceChar(c));
          return res * sgn;
      }
  
      public boolean isSpaceChar(int c) {
          if (filter != null)
              return filter.isSpaceChar(c);
          return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
      }
  
      public interface SpaceCharFilter {
          public boolean isSpaceChar(int ch);
      }
  }
  
  class OutputWriter {
      private final PrintWriter writer;
  
      public OutputWriter(OutputStream outputStream) {
          writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
      }
  
      public OutputWriter(Writer writer) {
          this.writer = new PrintWriter(writer);
      }
  
      public void print(Object...objects) {
          for (int i = 0; i < objects.length; i++) {
              if (i != 0)
                  writer.print(' ');
              writer.print(objects[i]);
          }
      }
  
      public void printLine(Object...objects) {
          print(objects);
          writer.println();
      }
  
      public void close() {
          writer.close();
      }
  
      }
  
  class IOUtils {
  
      public static int[] readIntArray(InputReader in, int size) {
          int[] array = new int[size];
          for (int i = 0; i < size; i++)
              array[i] = in.readInt();
          return array;
      }
  
      }
  
  class ArrayUtils {
      private static int[] tempInt = new int[0];
  
      public static int[] sort(int[] array, IntComparator comparator) {
          return sort(array, 0, array.length, comparator);
      }
  
      public static int[] sort(int[] array, int from, int to, IntComparator comparator) {
          ensureCapacityInt(to - from);
          System.arraycopy(array, from, tempInt, 0, to - from);
          sortImpl(array, from, to, tempInt, 0, to - from, comparator);
          return array;
      }
  
      private static void ensureCapacityInt(int size) {
          if (tempInt.length >= size)
              return;
          size = Math.max(size, tempInt.length << 1);
          tempInt = new int[size];
      }
  
      private static void sortImpl(int[] array, int from, int to, int[] temp, int fromTemp, int toTemp, IntComparator comparator) {
          if (to - from <= 1)
              return;
          int middle = (to - from) >> 1;
          int tempMiddle = fromTemp + middle;
          sortImpl(temp, fromTemp, tempMiddle, array, from, from + middle, comparator);
          sortImpl(temp, tempMiddle, toTemp, array, from + middle, to, comparator);
          int index = from;
          int index1 = fromTemp;
          int index2 = tempMiddle;
          while (index1 < tempMiddle && index2 < toTemp) {
              if (comparator.compare(temp[index1], temp[index2]) <= 0)
                  array[index++] = temp[index1++];
              else
                  array[index++] = temp[index2++];
          }
          if (index1 != tempMiddle)
              System.arraycopy(temp, index1, array, index, tempMiddle - index1);
          if (index2 != toTemp)
              System.arraycopy(temp, index2, array, index, toTemp - index2);
      }
  
      }
  
  interface IntComparator {
      public static final IntComparator DEFAULT = new IntComparator() {
          public int compare(int first, int second) {
              if (first < second)
                  return -1;
              if (first > second)
                  return 1;
              return 0;
          }
      };
  
      public int compare(int first, int second);
  }