import sys

class UnionFind(object):
    def __init__(self, n=1):
        self.par = [i for i in range(n)]
        self.rank = [0 for _ in range(n)]
        self.size = [1 for _ in range(n)]

    def find(self, x):
        if self.par[x] == x:
            return x
        else:
            self.par[x] = self.find(self.par[x])
            return self.par[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)
        if x != y:
            if self.rank[x] < self.rank[y]:
                x, y = y, x
            if self.rank[x] == self.rank[y]:
                self.rank[x] += 1
            self.par[y] = x
            self.size[x] += self.size[y]

    def is_same(self, x, y):
        return self.find(x) == self.find(y)

    def get_size(self, x):
        x = self.find(x)
        return self.size[x]

N = int(input())
A = list(map(int, input().split()))
U = UnionFind(N)
for i in range(N):
    U.union(i, A[i] - 1)
    
from collections import *
S = set()
D = defaultdict(int)
for i in range(N):
    ui = U.find(i)
    if ui in S:
        continue
    if U.get_size(i) % 2 == 0:
        D[U.get_size(i)] += 1
    S.add(ui)
       
for k, v in D.items():
    if v % 2:
        print("No")
        exit()
        
print("Yes")