n=int(input())
a=list(map(lambda x:int(x)-1, input().split()))
b=a.copy()
for i in range(n-2):
    b[i+1]=max(b[i+1],b[i])
ans=0
cur=0
while cur + 1 != n:
    cur=b[cur]
    ans+=1
print(ans)