RECURSION IN PROGRAMMING

 Recursion

Re-occurring process is called recursion. In recursion, function calls itself until the condition is satisfied.

Types of Recursion

        .     Direct / Indirect Recursion

        .     Tail / Non-Tail (Head) Recursion

        .     Linear / Non- Linear Recursion

Examples of recursion Implemented in C programming

Program to find the factorial of any number entered by user.

#include<stdio.h>

int fact(int n);

void main()

{

    int n,facto;

    printf("Enter a number");

    scanf("%d",&n);

    facto=fact(n);

    printf("the factorial is %d:",facto);

}

int fact(int n)

{

    if(n==0)

        return 1;

     else if(n==1)

       return 1;

     else

    return(n*fact(n-1));

}

Program to find the n^th  of Fibonacci series.

#include<stdio.h>

int fib(int);

void main()

{

 int n,fi;

 printf("Enter how many term");

 scanf("%d",&n);

 fi=fib(n);

 printf("The %d term is %d",n,fi);

}

int fib(int n)

{

    if(n==0||n==1)

        return n;

    else

        return (fib(n-1)+fib(n-2));

}

Program to find the product of two natural numbers.

#include<stdio.h>

int prdo(int,int);

void main()

{

    int a,b,pro;

    printf("Enter two natural number ");

    scanf("%d%d",&a,&b);

    pro=prdo(a,b);

    printf("The productt is %d",pro);

}

int prdo(int a , int b)

{

    if(b==1)

        return a;

    else

        return(a*(b-1)+a);

}