PRIME FACTORS

• Problem Description

  
  Helan had to find a number that must be the sum of two prime numbers. Help him to write a C Program to Check Whether a Number can be Expressed as Sum of Two Prime Numbers

• CODING ARENA::

• #include <stdio.h>

  int checkPrime(int n);

  int main()

  {

      int n, i, flag = 0;

  
  

      

      scanf("%d", &n);

  
  

      for(i = 2; i <= n/2; ++i)

      {

          

          if (checkPrime(i) == 1)

          {

             

              if (checkPrime(n-i) == 1)

              {

                 

                  printf("%d = %d + %d\n", n, i, n - i);

                  flag = 1;

              }

  
  

          }

      }

  
  

      if (flag == 0)

          printf("NOT");

  
  

      return 0;

  }

  
  

  
  

  int checkPrime(int n)

  {

      int i, isPrime = 1;

  
  

      for(i = 2; i <= n/2; ++i)

      {

          if(n % i == 0)

          {

              isPrime = 0;

              break;

          }  

      }

  
  

      return isPrime;

  }

• Test Case 1

  
  Input (stdin)

  35
  
  

  Expected Output

  NOT

• Test Case 2

  
  Input (stdin)

  34
  
  

  Expected Output

  34 = 3 + 31
  
  34 = 5 + 29
  
  34 = 11 + 23
  
  34 = 17 + 17