2815.Idempotent functions

Time Limit: 1s Memory Limit: 256MB

Some time ago Leonid have known about idempotent functions. Idempotent function defined on a set {1,2,...,n} is such function 2815_1.png, that for any 2815_2.png the formula g(g(x))=g(x) holds.Let's denote as f(k)(x) the function f applied k times to the value x. More formally, f(1)(x)=f(x), f(k)(x)=f(f(k-1)(x)) for each k \gt 1.You are given some function 2815_3.png. Your task is to find minimum positive integer k such that function f(k)(x) is idempotent.

Input Format(From the terminal/stdin)

Input In the first line of the input there is a single integer n (1 \le n \le 200) - the size of function f domain.In the second line follow f(1),f(2),...,f(n) (1 \le f(i) \le n for each 1 \le i \le n), the values of a function.

Output Format(To the terminal/stdout)

Output Output minimum k such that function f(k)(x) is idempotent.

Sample Input 1

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4
1 2 2 4
 \n
 · · · \n

Sample Output 1

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1
 \n

Sample Input 2

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3
2 3 3
 \n
 · · \n

Sample Output 2

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2
 \n

Sample Input 3

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3
2 3 1
 \n
 · · \n

Sample Output 3

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3
 \n

Hints

In the first sample test function f(x)=f(1)(x) is already idempotent since f(f(1))=f(1)=1, f(f(2))=f(2)=2, f(f(3))=f(3)=2, f(f(4))=f(4)=4.In the second sample test: function f(x)=f(1)(x) isn't idempotent because f(f(1))=3 but f(1)=2; function f(x)=f(2)(x) is idempotent since for any x it is true that f(2)(x)=3, so it is also true that f(2)(f(2)(x))=3. In the third sample test: function f(x)=f(1)(x) isn't idempotent because f(f(1))=3 but f(1)=2; function f(f(x))=f(2)(x) isn't idempotent because f(2)(f(2)(1))=2 but f(2)(1)=3; function f(f(f(x)))=f(3)(x) is idempotent since it is identity function: f(3)(x)=x for any 2815_4.png meaning that the formula f(3)(f(3)(x))=f(3)(x) also holds.

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