Ackermann Function Evaluation

This problem asks you to evaluate the Ackermann function \( A(m, n) \) for given non-negative integers \(m\) and \(n\). The function is defined by:

\( A(m, n) = n + 1 \)     (if \( m = 0 \));

\( A(m, n) = A(m-1, 1) \)     (if \( m > 0 \) and \( n = 0 \));

\( A(m, n) = A(m-1, A(m, n-1)) \)     (if \( m > 0 \) and \( n > 0 \)).

Constraints: \( m \) and \( n \) are non-negative integers. It is guaranteed that \( m \le 3 \) and \( n \le 10 \).

inputFormat

The input consists of two space-separated integers \( m \) and \( n \).

outputFormat

Output the value of the Ackermann function \( A(m, n) \) computed using the above recursive definition.

sample

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