Prime Number By Recursion Method Using C Program

 

#include<stdio.h>

#include<conio.h>

#include<math.h>

int prime(int n, int i)

{

    if(i<=sqrt(n))

    {

        if(n%i==0)

            return(i);

        i=prime(n,i+1);     //Recursion: Function calling itself

    }

    //printf("%d",i);

    return(i);

}

int main()

{                        

    int n,t;

    char ans;

    //clrscr();

    do{

    printf("\n enter any number: ");

    scanf("%d",&n);

    t=prime(n,2);

    if(t>sqrt(n))

        printf("\n your number %d is prime number",n);

    else

        printf("\n your number %d is not prime",n);

    fflush(stdin);        //clean the garbage of standard input stream before taking input

    printf("\n Want to continue (y/n): ");

    scanf("%c",&ans);

    }while(ans=='y'||ans=='Y');

    //getch();                             //use getch() in TurboC++ to hold the console

    return 0;

}