Thursday, November 21, 2019

Twisted Prime Number upto a Given Range Program and Algorithm


A number is said to be a Twisted Prime Number if its reverse is also a prime number. As for Example: 2, 11, 101, 107, 113, 149, 151 etc are Twisted Prime Numbers.
As for example let us consider about number 107. 107 is a Prime Number and its reverse 701 too is also a prime number. 
For printing Twisted Prime numbers, we have to check whether each number and its reverse from 1 to RANGE (as assigned by the user) as Prime. If it is a prime number and its reverse is too, then it will be printed. For this we have taken two functions as follows:

FUNCTIONS USED:
check_prime(number) : Check whether "number" is prime or not. This function returns 1, if "number" is prime.
reverse(number): for reversing "number". This function returns the reverse of "number".


ALGORITHMS:
main( )
{
   input: RANGE;

   set: number1=1, number2;   
while(number1<=RANGE)
{
   number2 = reverse(number1);
   if(check_prime(number1))
   {
        if(check_prime(number2))
        {
             Print: number1;
        }
   }
   number1=number1+1;
}


PROGRAM:
#include<stdio.h>
int check_prime(int);
int reverse(int);
void main()
{
  int RANGE, number1=1, number2;
  //printf("Enter Range:");
  scanf("%d", &RANGE);
  while(number1<=RANGE)
  {
    number2=reverse(number1);
    if(check_prime(number1))
    {
     if(check_prime(number2))
      {
        printf("\n%d", number1);
      }
    }
    number1=number1+1;
  }
}
int reverse(int K)
{
  int i, s=0;
  while(K!=0)
   {
    i=K%10;
    s=s*10+i;
    K=K/10;
   }
  return s;
}

int check_prime(int Q)
{
  int x=1, c=0;
  while(x<=Q)
  {
    if(Q%x==0)
    {
      c=c+1;
    }
    x=x+1;
  }
  if(c==2)
  {
    return 1;
  }
  else
  {
    return 0;
  }
}


RUN PROGRAM

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1 comment:

  1. Is there any link to download all program?

    ReplyDelete