Single Flip


Given two permutations \(A\) and \(B\) of length \(N\). You have to select an index \(x\) (\(1 \le x \le N\)) and swap the values of \(A_x\) and \(B_x\). Count the number of indices \(x\) that allows \(A\) and \(B\) to remain as permutations after swapping the index.

Note: A permutation of length \(N\) is a sequence of \(N\) integers from \(1\) to \(N\) such that each element appears exactly once in the sequence.


  • \(1 \le N \le 100\)
  • \(1 \le A_i \le N\)
  • \(1 \le B_i \le N\)
  • \(A\) and \(B\) are permutations.


A1 A2 … AN
B1 B2 … BN


A single integer representing the number of indices such that \(A\) and \(B\) remain as permutations after swapping.

Sample Input

1 2 3 4 5
5 2 3 1 4

Sample Output



We can select indices \(2\) or \(3\), and both \(A\) and \(B\) will remain as permutations after swapping.

Submitting .cpp to 'Single Flip'

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Compile Errors

Time Limit: 1 Seconds
Memory Limit: 1024MB
No. of ACs: 21
Your best score: 0
Source: TROC 24 (maomao90)

Subtask Score
1 100