🚀 Programming Example

Command Line Program to Check if a Number is Palindrome or Not using C Programming language

👁 1,001 Views

💻 Practical Program

📘 Step Learning

Program to check whether the given number is a palindrome or not is discussed here. Any number is said to be a palindrome if the original number and the reverse of the original number are the same.

For example, 1234321 is a palindrome.

Original number = 1234321
The reverse of the number = 1234321

Algorithm to check whether a number is a palindrome or not

Input the number.
Find the reverse of the number.
If the reverse of the number is equal to the number, then return true. Else, return false.

💻 Program Code

#include <stdio.h>

int main(int argc, char *argv[])
{
            int num, reverse_num=0,remainder,temp;
            num = atol(argv[1]);
            temp=num;

            while(temp!=0)
           {
            remainder=temp%10;
            reverse_num=reverse_num*10+remainder;
            temp/=10;
           }
   
   if(reverse_num==num)
            printf("%d is a palindrome number",num);
   else
            printf("%d is not a palindrome number",num);
   return 0;
}

🖥 Program Output

11

11 is a palindrome number
<hr>

121

121 is a palindrome number

📘 Explanation

Program without command line arguments


// program by atnyla coder

#include<stdio.h>
void main()
{

int number, temp, remainder;
int sum = 0;
printf("Enter a number to check for palindrome. ");
scanf("%d", &number);

temp = number;

while(temp != 0)
{
	remainder = temp % 10;
	sum = sum*10 + remainder;
	temp = temp / 10;
}

if(sum == number)
{
	printf("Number is palindrome");
}
else{
	printf("Number is not palindrome");
}

}

Palindrome or not using a recursive approach


#include<stdio.h>

int is_Palindrome(int );

int n;

int main()
{
	int palindrome;
	printf("\n\nEnter a number : ");
	scanf("%d", &n);
	palindrome = is_Palindrome(n);
	
	if(palindrome == 1)
		printf("\n%d is palindrome\n", n);
	else
		printf("\n%d is not palindrome\n", n);

return 0;
}

int is_Palindrome(int aj)
{
	static int sum = 0;
	if(aj != 0)
	{
		sum = sum *10 + aj%10;
		is_Palindrome(aj/10); // recursive call
	}
	else if(sum == n)
		return 1;
	else
		return 0;
}

🎯 How to learn from this example

First understand the algorithm carefully. Then study the program line-by-line and compare it with the output. Finally, review the explanation section to strengthen your logic and programming understanding.

🔥 Practice suggestion

Rewrite the program without looking at the code. Modify values, conditions or logic and run it again. This helps improve confidence and strengthens coding skills much faster.