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C++/C++ programme


Write a single recursive function in C++ that computes Ackerman's function. Do not use
other functions or loops. Assume parameters m and n passed are always greater or equal to zero.

int ackerman(int m, int n) { }


Ackerman's function is defined as follows:

A(0, j)=j+1 for j 0
A(i, 0)=A(i-1, 1) for i > 0
A(i, j)=A(i-1, A(i, j-1)) for i, j > 0

To implement it, you need to consider thre cases. Two cases are special cases (when i is zero, or when j is zero). The other case is general (when i and j are not zero).
In recursive functions, the function gets called from inside. For instance:

int ackerman(int m, int n)
 if(m != 0 && n != 0){
   return ackerman(m-1, n-1);

In recursive functions, you should always take care of the special cases separately.
I hope this helps. Please let me know if you need further assistance with this concept. If you need assistance with coding recursive functions, you may email They can help you with coding and implementation issues.


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