Problem Description

One day dandelion and her friends decides to play outside. As there are so many people , they decide to divide into several parts . Dandelion wants to know how many friends will be together with her. The way they use to divide is : everyone can choose one people to join in her group, Such as if A chooses B to join in her group , then B will leave the group she is in now , and joins in the group that A is in . One can also choose some people who has already in her group. All of dandelion抯 friends are expressed as an integer 2,3... n and dandelion is expressed as 1.The choosing work begins from dandelion then the friend who are signed as 2 ?until the friend who are signed as n .

Input

Each case begins with an integer n, (0<n<=1000000) stands for the number of people.
Then follows n lines , the i+1 line contains an integer p, stands for people who are signed as i chooses the one who are signed as p to join in her group.

Output

The output contains one line for each data set : the number of friends will be together with dandelion at last .

3
3
3
1
3
2
1
2

2
0

Hint

Hint
For the second case , the group is (1)(2)(3) at first , then (1,2)(3) after dandelion抯 picking , then ( 1 , 2 ) ( 3) , then (1) (2 ,3). So at last , no other people is together with dandelion.

Author

dandelion