## Mock CCC '19 Contest 1 J5 - One-way Hopscotch

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Points: 7 (partial)
Time limit: 2.0s
Memory limit: 64M

Author:
Problem type

You are playing hopscotch on a one-indexed array of integers. You can choose to start at some index (which is undecided). Your goal is to reach index . This game of hopscotch is strange. At index , it is already defined where you must hop to. At index , you must hop to index .

You want to find out, for how many starting indices will you be able to reach index ?

#### Input Specification

The first line will contain the integer , the number of elements.

The second line will contain integers, .

#### Output Specification

Output the number of starting indices where you will be able to reach index .

#### Subtasks

For 3/15 of the points, .

For an additional 4/15 of the points, .

#### Sample Input

6
5 2 2 2 3 1

#### Sample Output

4

#### Explanation For Sample

You will be able to reach index when starting at indices or .