## C Program to reverse a given number using Recursive function

June 5, 2021 In this tutorial, we will learn following two methods of reversing a number.
1) Using Recursion
2) Using While loop

### Reverse a given number using Recursion:

In this program, we are calling a user defined function “reverse_function”, the function is calling itself recursively.

```#include<stdio.h>
int main(){
int num,reverse_number;

//User would input the number
printf("\nEnter any number:");
scanf("%d",&num);

//Calling user defined function to perform reverse
reverse_number=reverse_function(num);
printf("\nAfter reverse the no is :%d",reverse_number);
return 0;
}
int sum=0,rem;
reverse_function(int num){
if(num){
rem=num%10;
sum=sum*10+rem;
reverse_function(num/10);
}
else
return sum;
return sum;
}```

Output:

```Enter any number: 23456
After reverse the no is :65432```

### Reversing a number using While loop

In the above program we learnt how to reverse a number using recursive function. Here we would learn how to do it using while loop.

```#include<stdio.h>
int main()
{
int num,rem,reverse_num=0;
//Input number
printf("\nEnter any number:");
scanf("%d",&num);

while(num>=1)
{
rem = num % 10;
reverse_num = reverse_num * 10 + rem;
num = num / 10;
}

printf("\nReverse of input number is: %d", reverse_num);
return 0;
}```

Output:

```Enter any number: 49212
Reverse of input number is: 21294```