source_code: import java.io.InputStreamReader;
  import java.io.IOException;
  import java.io.BufferedReader;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.util.StringTokenizer;
  import java.io.InputStream;
  
  /**
   * Built using CHelper plug-in
   * Actual solution is at the top
   * @author Sunits789
   */
  public class Main {
  	public static void main(String[] args) {
  		InputStream inputStream = System.in;
  		OutputStream outputStream = System.out;
  		InputReader in = new InputReader(inputStream);
  		PrintWriter out = new PrintWriter(outputStream);
  		TaskA solver = new TaskA();
  		solver.solve(1, in, out);
  		out.close();
  	}
  }
  
  class TaskA {
  	public void solve(int testNumber, InputReader in, PrintWriter out) {
          int n=in.nextInt();
          int arr[]=new int[n];
          in.getArray(arr);
          int arrc[]=new int[n];
          for(int i=0;i<n;i++){
              arrc[i]=arr[i];
          }
          Library.sort(arrc);
          int c=0;
          for(int i=0;i<n;i++){
              if(arrc[i]!=arr[i]){
                  c++;
              }
          }
          if(c>2){
              out.println("NO");
          }
          else{
              out.println("YES");
          }
  	}
  }
  
  class InputReader{
      private BufferedReader reader;
      private StringTokenizer tokenizer;
  
      public InputReader(InputStream stream){
          reader = new BufferedReader(new InputStreamReader(stream));
          tokenizer = null;
      }
      public String next(){
          while (tokenizer == null||!tokenizer.hasMoreTokens()){
              try{
                  tokenizer = new StringTokenizer(reader.readLine());
              }
              catch (IOException e){
                  throw new RuntimeException(e);
              }
          }
          return tokenizer.nextToken();
      }
  
      public int nextInt(){
          return Integer.parseInt(next());
      }
  
      public void getArray(int arr[]){
          for(int i=0;i<arr.length;i++){
              arr[i]=nextInt();
          }
      }
  
      }
  
  class Library{
      public static void sort(int n[]){
          int len=n.length;
          int l1=len/2;
          int l2=len-l1;
          int n1[]=new int[l1];
          int n2[]=new int[l2];
          for(int i=0;i<l1;i++){
              n1[i]=n[i];
          }
          for(int i=0;i<l2;i++){
              n2[i]=n[i+l1];
          }
          if(l1!=0){
              sort(n1);
              sort(n2);
          }
          int ind1=0;
          int ind2=0;
          int ind=0;
          for(int i=0;i<len&&ind1<l1&&ind2<l2;i++){
              if(n1[ind1]<n2[ind2]){
                  n[i]=n1[ind1];
                  ind1++;
              }
              else{
                  n[i]=n2[ind2];
                  ind2++;
              }
              ind++;
          }
          if(ind1<l1){
              for(int i=ind1;i<l1;i++){
                  n[ind]=n1[i];
                  ind++;
              }
          }
          if(ind2<l2){
              for(int i=ind2;i<l2;i++){
                  n[ind]=n2[i];
                  ind++;
              }
          }
      }
      
      }
  
  