n=int(input())
ns=list(map(int,input().split()))
m=[0]*(n-1)
ma=0
for i in range(n-1):
    ma=max(ns[i],ma)
    m[i] = ma
    
now=m[0]
cnt=1
while now != n:
    now = m[now-1]
    cnt+=1
print(cnt)