C++ Program For Converting A User Entered Number Into A Single Digit.

This Post Contains A C++ Program For Converting A User Entered Number Into A Single Digit With Correct Source Code & Output. This Program Is Written, Compiled & Executed At TurboC/C++3.0 Compiler & Will Help You To Understand The Concept Of 'Do...While-Loop', 'While-Loop' & 'Nested Loops' 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 For Converting A User Entered Number Into A Single Digit.

/* Declaration Of Header Files */
#include<iostream.h>
#include<conio.h>

/* Start Of Main Program */
void main()
{
 /* Declaration Of Variables */
 int s, r, a[10], i;
 long Num, Temp;
 clrscr();

 /* Asking For The Input From User */
 cout << " \n Enter Any Number : ";
 cin >> Num;
 Temp=Num;

 /* Source Code For Computing Converting User Entered Number, i.e 'Num' Into A Single Digit */
 do
 {
  i=s=0;
  while(Num>0)
  {
   r=Num%10;
   a[i]=r;
   s=s+r;
   i++;
   Num=Num/10;
  }
  --i;
  if(i!=0)
  {
   Num=s;
  }
  if(i==0 || i==1)
  {
   cout << " \n Answer After Converting " << Temp << " Into A Single Digit Is : " << s;
   break;
  }
 }while(i>0);

getch();
}
/* End Of Main Program */

Output :

Enter Any Number  :  12345
[1+2+3+4+5] = 15 = [1+5] = 6
Answer After Converting 12345 Into A Single Digit Is  :  6