import java.util.Scanner;


public class Main0100 {
	public static void main(String[] args) {
		Main0100 p = new Main0100();
	}

	public Main0100() {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int[] a = new int[n];
		for (int i = 0; i < a.length; i++)
			a[i] = sc.nextInt()-1;
		solve(n, a);
	}

	public void solve(int n, int[] a) {
		boolean res = true;
		uf(n);
		for(int i=0;i<a.length;i++){
			unite(i, a[i]);
		}
		
		int gc = 0;
		boolean[] isVisit = new boolean[n];
		for(int i=0;i<n;i++){
			if(isVisit[i])
				continue;
			
			int c = 0;
			isVisit[i] = true;
			for(int j=0;j<n;j++){
				if(same(i, j)){
					isVisit[j] = true;
					c++;
				}
			}
			if(c%2==0){
				gc++;
			}
		}
		
		System.out.println(gc%2==0 ? "Yes" : "No");
	}
	
	
	int[] par;
	int[] rank;
	private void uf(int n){
		par = new int[n];
		rank = new int[n];
		for(int i=0;i<n;i++){
			par[i] = i;
			rank[i] = 0;
		}
	}
	
	// 木の根を返す
	private int find(int x){
		if(par[x] == x)
			return x;
		else
			return par[x] =find(par[x]);
	}
	
	// 併合
	private void unite(int x, int y){
		x = find(x);
		y = find(y);
		
		// すでに同じグループ
		if(x==y)
			return;
		
		if(rank[x]<rank[y]){
			par[x] = y;
		}else{
			par[y] = x;
			if(rank[x]==rank[y])
				rank[x]++;
		}
	}
	
	// 同じグループなら真
	private boolean same(int x, int y){
		return find(x) == find(y);
	}	
}