import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int[] p = new int[n];
		int[] firstP = new int[n];
		for(int i=0;i<n;i++){
			p[i] = sc.nextInt();
		}
		sc.close();
		
		for(int i=0;i<n;i++){
			firstP[i] = p[i];
		}
		
		Arrays.sort(p);
		
		int count = 0;
		
		for(int i=0;i<n;i++){
			if(p[i]!=firstP[i]){
				count++;
			}
		}
		if(count==0||count==2){
			System.out.println("YES");
		}else{
			System.out.println("NO");
		}
	}
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz