C Program to Reverse a given Number

In this tutorial, we are going to write a C Program to Reverse a given number in C Programming with practical program code and step-by-step full complete explanation.

C Program to Reverse a given Number.

#include <stdio.h>
#include <conio.h>

void main()
{
	int n,a,r=0;

	clrscr();

	printf("Enter any number to print it reverse: ");
	scanf("%d",&n);

	while(n>=1)
	{
	a = n%10;
	r=r*10+a;
	n=n/10;
	}

	printf("Reverse = %d",r);

	getch();
}

Output

Enter any number to print it reverse: 456
Reverse = 654

Here in the above program to reverse a given number we use the while loop. and it will run till the value of n is greater than or equal to 1. and in the logic part, we first find the modulo 10 of the given number to extract the last number from the given number. and then we multiply it by 10. and store it in r variable. just like

456 % 10 = 6

r = 0*10 + 6 = 6

and then divide the number by 10 to get the other numbers and store it in the n variable again. just like

n = 456 / 10 = 45

n = 45

and then we again use conditions to get the last number from the n.