import sys
input=lambda:sys.stdin.readline().rstrip()
N=int(input())
A=list(map(lambda x:int(x)-1,input().split()))
cycle=[0 for i in range(N+1)]
checked=[0 for i in range(N)]
for i in range(N):
	if not checked[i]:
		cnt,pt=0,i
		while not checked[A[pt]]:
			pt=A[pt]
			checked[pt]=1
			cnt+=1
		if cnt%2==0:
			cycle[cnt]=1-cycle[cnt]
print(["Yes","No"][max(cycle)])