How to use recursion...

[shankvee]

Can someone please help me with recursion i have no clue how to use it and have never used recursion before
suppose you have a M by N grid how do you compute all squares that can be obtained from this grid using recursion?? Please explain in simple terms?

[Gaminic]

Recursion is any function that calls itself. All it needs is a body and a termination condition.
For example, to count down from 5 to 0 recursively:

void countDown(int n) {
    if (n == 0) { printf("%d!", 0); return; }
    printf("%d... ", n);
    countDown(n-1);
}

The termination condition (n == 0) makes sure it stops at some point, by quitting before doing another recursive call to countDown.

[shankvee]

So your code just prints n to 1? Hmmm... Looks good...
Please give me some time i will think abt how to do the given problem thanks a lot... :)

[Michael McCody]

An example :

#include <iostream>
  using namespace std;
  
  int factorial(int n)    // 1, 1, 2, 6, 24, 120, 720, ...  
  {
    if (n == 0) return 1;
    return n * factorial(n-1);
  }

  main()
  {
    int n=7;
   
    //cout << "Enter a non-negative integer: ";
    //cin >> n;
    cout << "The Factorial of " << n << " is " << factorial(n) << endl;  
    return 0;
  }