## Print Natural Numbers In Reverse Using While Loop C Program

In this tutorial, you will learn how to write a C program to print all natural numbers in reverse order using a while loop conditional statement. We will explore examples and algorithms with explanations for your better understanding of this problem.

## Problem Statement

You have to Write a C Program that prints all natural numbers in reverse order using a while loop. The program provides a solution to print natural numbers in reverse order using a while loop in the C programming language. For a better understanding, you can see the below example. It will help you to understand what exactly you have to achieve.

Example

``````Output:
10
9
8
7
6
5
4
3
2
1``````

Here the input is not given by the user. We have kept the hardcoded value 10 and printed them in reverse order.

## Algorithm

1. Start the program.
2. Declare the variable `num` to store the current number.
3. Initialize `num` to 10.
4. Enter the while loop with the condition `num >= 1`.
• Print the value of `num`.
• Decrement `num` by 1.
5. Exit the while loop.
6. End the program.

## Logic used to solve this problem

• Declare a variable to hold the maximum limit of the natural numbers.
• Prompt the user to enter the maximum limit.
• Read and store the entered maximum limit in the variable.
• Initialize a counter variable with the maximum limit.
• Use a while loop that runs as long as the counter is greater than or equal to 1.
• Inside the loop, print the value of the counter.
• Decrement the counter by 1 in each iteration.
• Continue the loop until the counter becomes less than 1.
• Finish the program.

## Program to Print all Natural numbers in Reverse Order

``````#include <stdio.h>
int main() {
int num = 10;
while (num >= 1) {
printf("%d\n", num);
num--;
}
return 0;
}``````

Output

``````10
9
8
7
6
5
4
3
2
1``````

### Program Explanation

• The program takes input for the value of n from the user.
• It initializes a variable `num` to n, which represents the starting point for printing the numbers.
• The program enters a while loop with the condition `num >= 1` to iterate through numbers from n to 1.
• Inside the while loop, it prints the value of `num` on the screen.
• It then decrements the value of `num` by 1 to move on to the next number in reverse order.
• The loop continues until `num` reaches 1.
• Once the while loop is complete, the program ends.

## Conclusion

The C program successfully prints all natural numbers in reverse order using a while loop. By starting with an initial value and decrementing it in each iteration, the program displays the numbers in descending order on the screen.