Assignment 4 Solutions

CSCI 262 Data Structures--Spring 2004

Assignment 4 Solutions
Solution ackermann.cc code:
/*******************************************************************
* Name: Brenda Student
* Date: 3/15/04
* Course: CSCI 262 Section 01
* Assignment: Assignment 4
* Instructor: Royden
* Program: ackermann.cc
* Purpose:  A program that finds the output of the ackermann function
* for two integer inputs, m and n.
***************************************************************************/
#include <iostream.h>
int ackerman(int, int);

int main(void) {
  int n, m;	//input integers
  
  cout << "Enter positive integer for m: ";
  cin >> m;

  cout << "Enter positive integer for n: ";
  cin >> n;

  cout << "The ackerman value is " << ackerman(m, n) << "." << endl;
}

/*************************************************************************
* int ackerman(int, int)
* Purpose: A recursive program to compute the output of the Ackermann function.
* Pre: m and n are positive integers
* Post: returns the value of the ackerman function for inputs m and n
**************************************************************************/
int ackerman(int m, int n) {
  if ((m == 0) ) {
    return n + 1;
  } else if (n == 0) {
    return ackerman(m - 1, 1);
  } else {
    return ackerman(m-1, ackerman(m, n-1));
  }
}