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Write a program that prompts the user to input a positive integer. It should then output a message indicating whether the number is a prime number.
(Note: An even number is prime if it is 2. An odd integer is prime if it is not divisible by any odd integer less than or equal to the square root of the number.)

Turn in:

Your source code for with

The name of your program as a comment at the top of the file

Your IPO chart incorporated as comments after the name of the file

A screen shot or picture of the results after running your program with your test data.

Answer 1

==========================================

#include<iostream>
int main()
{
   //Declare all required variables
   int n;
   int count=0;
  
   cout<<"Enter a number: ";
   cin>>n;
  
   //Check all the numbers from 1 to n are divisible by given number
   for(int i=1;i<=n;i++)
   {
       //Condition to check number is divisible by current i
       if(n%i==0)
       {
           //If divisible increment counter
           count= count+1;
       }
   }
  
   //If count is 2 it is prime number  
   if(count==2)
   {
       cout<<n<<" is a prime number."<<endl;
   }
   else
   {
       cout<<n<<" is not a prime number."<<endl;
   }
  
   return 0;
}
  

      
==================================================================  
IPO CHART:

   --------
   Input:
   --------  
       Enter a number n
  
   -------------
   Processing:
   -------------
       Determine if the given number is prime or not using division of each number <=n by below logic
       //Check all the numbers from 1 to n are divisible by given number
       for(int i=1;i<=n;i++)
       {
           //Condition to check number is divisible by current i
           if(n%i==0)
           {
               //If divisible increment counter
               count= count+1;
           }
       }

   ----------
   Output:
   ----------
      
       If the count ==2 , display prime
       else display not a prime
      
==================================================================