C++ Program To Find A Prime Number.

This Post Contains A C++ Program To Find A Prime Number With Correct Source Code & Output. This Program Is Written, Compiled & Executed At TurboC3.0 Compiler & Will Help You To Understand The Concept Of 'While-loop' & 'If...else' From C++ Language. It Is A Well-Structured Program With Proper Comments Which Provides Step-By-Step Description Of Various Features Of The Language In A Simple & Easy-To-Understand Way.

# Note : You Can Simply Copy-Paste The Following Program Or Code Into Compiler For Direct Result.


C++ Program To Find A Prime Number.

# include <iostream.h>
# include <conio.h>

void main()
{
   int Num = 0, k, i;
   clrscr();
   cout << " Enter Any Number : ";
   cin >> Num;
   i = 1, k = 0;
   while ( i <= Num )
   {
      if ( Num % i == 0 )
         k++;
         i++;
   }
   if ( k == 2 )
   {
      cout << Num << " Is A Prime Number. ";
   }
   else
   {
      cout << Num << " Is Not A Prime Number. ";
   }
   getch();
}

Output :

Enter Any Number  :  5

5 Is A Prime Number.

Enter Any Number  :  9

9 Is Not A Prime Number.