# Reverse of a Number using do-while loop in C++

## Program code to find Reverse of a Number:

#include<iostream.h> #include<conio.h> void main() { int n,a,r,s=0; clrscr(); cout<<"\n Enter The Number:"; cin>>n; a=n; //LOOP FOR FINDING THE REVERSE OF A NUMBER do { r=n%10; s=s*10+r; n=n/10; }while(n>0); cout<<"\n The Reverse Number of "<<a<<" is "<<s; getch(); }

**Related: **Reverse of a Number using do-while loop in C

## Working:

- First the computer reads a number from the user.
- Then using do-while loop the reverse number is calculated and stored in the variable ‘s’.
- Finally the reverse of a given number is printed.

## Step by step working of the above C++ program:

Let us assume a number entered is **4321.**

So n=4321 , s=0

- r=n%10 (r=4321%10) So r=1

s=s*10+r (s=0*10+1) So s=1

n=n/10 (n=4321/10) So n=432

- n>0 (123>0) do-while loop condition is true

r=n%10 (r=432%10) So r=2

s=s*10+r (s=1*10+2) So s=12

n=n/10 (n=432/10) So n=43

- n>0 (12>0) do-while loop condition is true

r=n%10 (r=43%10) So r=3

s=s*10+r (s=12*10+3) So s=123

n=n/10 (n=43/10) So n=4

- n>0 (1>0) do-while loop condition is true

r=n%10 (r=4%10) So r=4

s=s*10+r (s=123*10+4) So s=1234

n=n/10 (n=4/10) So n=0

- n>0 (0>0) do-while loop condition is false

It comes out of the do-while loop and prints the reverse number which is stored in variable “s”.

- Thus the program execution is completed.

## Output:

### TO DOWNLOAD THE PROGRAM CODE : CLICK HERE

out class wonder full

thanks very much i love it