# C Exercises: Find next smallest palindrome of a given number

## C Programming Mathematics: Exercise-23 with Solution

Write a C program to find next smallest palindrome of a given number.

From Wikipedia,

A palindrome is a word, number, phrase, or other sequence of characters which reads the same backward as forward, such as madam, racecar. There are also numeric palindromes, including date/time stamps using short digits 11/11/11 11:11 and long digits 02/02/2020. Sentence-length palindromes may be written when allowances are made for adjustments to capital letters, punctuation, and word dividers, such as "A man, a plan, a canal, Panama!".

Example:

Input: n = 121

Output: Next smallest palindrome of 121 is 131

**Visual Presentation:**

**Sample Solution:**

**C Code:**

```
#include <stdio.h>
#include <stdlib.h>
// Function to generate the next smallest palindrome after 'n'
int nextPalindromeGenerate(int n)
{
int ans=1, digit, rev_num=0, num; // Declare variables ans, digit, rev_num, and num
if(n<10) // Check if n is less than 10
{
ans=0; // Set ans to 0
return n+1; // Return n+1 as the next smallest palindrome
}
num=n; // Store the original value of n
while(ans!=0) // While loop until ans is not 0
{
rev_num=0; // Initialize rev_num to 0
digit=0; // Initialize digit to 0
n=++num; // Increment num and assign to n
while(n>0) // While loop to reverse the number and store it in rev_num
{
digit=n%10; // Get the last digit of n
rev_num=rev_num*10+digit; // Append digit to rev_num
n=n/10; // Remove the last digit from n
}
if(rev_num==num) // Check if the reversed number is equal to the original number
{
ans=0; // Set ans to 0
return num; // Return the palindrome number
}
else
ans=1; // Set ans to 1 to continue the loop
}
return num; // Return the next palindrome number
}
int main(void)
{
int n = 121; // Declare and initialize n to 121
if (n>0); // Check if n is positive (semicolon here may cause unexpected behavior, it's better to remove it)
{
printf("Next smallest palindrome of %d is %d", n, nextPalindromeGenerate(n)); // Print the next smallest palindrome of n
}
return 0; // Return 0 to indicate successful execution
}
```

Sample Output:

Next smallest palindrome of 121 is 131

**Flowchart: **

**C Programming Code Editor:**

**Improve this sample solution and post your code through Disqus.**

**Previous:** Write a C program to count the numbers without digit 7, from 1 to a given number.

**Next:** Write a C program to calculate e raise to the power x using sum of first n terms of Taylor Series.

**What is the difficulty level of this exercise?**

Test your Programming skills with w3resource's quiz.

**Weekly Trends and Language Statistics**- Weekly Trends and Language Statistics