Sum of all palindrome numbers present in an Array

Given an array arr[] of N positive integers. The task is to find the sum of all palindrome numbers present in the array. Print the total sum.

A palindrome number is a number which when reversed is equal to the initial number. Example: 121 is palindrome(reverse(121) = 121), 123 is not palindrome(reverse(123) = 321).

Note: Consider palindrome numbers of length greater than 1 while calculating the sum.

Examples:

Input : arr[] ={12, 313, 11, 44, 9, 1} 
Output : 368

Input : arr[] = {12, 11, 121}
Output : 132

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: The idea is to implement a reverse function that reverses a number from the right to left. Implement a function that checks for palindrome numbers and finally traverse the array and calculate sum of all elements which are palindrome.

Below is the implementation of the above approach:

C++

// C++ program to calculate the sum of all 
// palindromic numbers in array 
#include<bits/stdc++.h> 
using namespace std; 
  
// Function to reverse a number n 
int reverse(int n) 
{ 
    int d = 0, s = 0; 
  
    while (n > 0)  
    { 
        d = n % 10; 
        s = s * 10 + d; 
        n = n / 10; 
    } 
  
    return s; 
} 
  
// Function to check if a number n is 
// palindrome 
bool isPalin(int n) 
{ 
    // If n is equal to the reverse of n 
    // it is a palindrome 
    return n == reverse(n); 
} 
  
// Function to calculate sum of all array 
// elements which are palindrome 
int sumOfArray(int arr[], int n) 
{ 
    int s = 0; 
  
    for (int i = 0; i < n; i++)  
    { 
        if ((arr[i] > 10) && isPalin(arr[i]))  
        { 
  
            // summation of all palindrome numbers 
            // present in array 
            s += arr[i]; 
        } 
    } 
    return s; 
} 
  
// Driver Code 
int main() 
{ 
    int n = 6; 
  
    int arr[] = { 12, 313, 11, 44, 9, 1 }; 
  
    cout << sumOfArray(arr, n); 
    return 0; 
} 
  
// This code is contributed by mits 

Java

// Java program to calculate the sum of all 
// palindromic numbers in array 
  
class GFG { 
  
    // Function to reverse a number n 
    static int reverse(int n) 
    { 
        int d = 0, s = 0; 
  
        while (n > 0) { 
            d = n % 10; 
            s = s * 10 + d; 
            n = n / 10; 
        } 
  
        return s; 
    } 
  
    // Function to check if a number n is 
    // palindrome 
    static boolean isPalin(int n) 
    { 
        // If n is equal to the reverse of n 
        // it is a palindrome 
        return n == reverse(n); 
    } 
  
    // Function to calculate sum of all array 
    // elements which are palindrome 
    static int sumOfArray(int[] arr, int n) 
    { 
        int s = 0; 
  
        for (int i = 0; i < n; i++) { 
            if ((arr[i] > 10) && isPalin(arr[i])) { 
  
                // summation of all palindrome numbers 
                // present in array 
                s += arr[i]; 
            } 
        } 
  
        return s; 
    } 
  
    // Driver Code 
    public static void main(String[] args) 
    { 
        int n = 6; 
  
        int[] arr = { 12, 313, 11, 44, 9, 1 }; 
  
        System.out.println(sumOfArray(arr, n)); 
    } 
} 

C#

// C# program to calculate the sum of all  
// palindromic numbers in array  
using System; 
  
class GFG  
{  
  
    // Function to reverse a number n  
    static int reverse(int n)  
    {  
        int d = 0, s = 0;  
  
        while (n > 0) 
        {  
            d = n % 10;  
            s = s * 10 + d;  
            n = n / 10;  
        }  
  
        return s;  
    }  
  
    // Function to check if a number n is  
    // palindrome  
    static bool isPalin(int n)  
    {  
        // If n is equal to the reverse of n  
        // it is a palindrome  
        return n == reverse(n);  
    }  
  
    // Function to calculate sum of all array  
    // elements which are palindrome  
    static int sumOfArray(int[] arr, int n)  
    {  
        int s = 0;  
  
        for (int i = 0; i < n; i++) 
        {  
            if ((arr[i] > 10) && isPalin(arr[i])) 
            {  
  
                // summation of all palindrome numbers  
                // present in array  
                s += arr[i];  
            }  
        }  
  
        return s;  
    }  
  
    // Driver Code  
    public static void Main(String[] args)  
    {  
        int n = 6;  
  
        int[] arr = { 12, 313, 11, 44, 9, 1 };  
  
        Console.WriteLine(sumOfArray(arr, n));  
    }  
}  
  
/* This code contributed by PrinciRaj1992 */

Python3

# Python3 program to calculate the sum of all 
# palindromic numbers in array 
  
# Function to reverse a number n 
def reverse(n) : 
      
    d = 0; s = 0; 
  
    while (n > 0) : 
  
        d = n % 10; 
        s = s * 10 + d; 
        n = n // 10; 
  
    return s; 
      
  
# Function to check if a number n is 
# palindrome 
def isPalin(n) : 
  
    # If n is equal to the reverse of n 
    # it is a palindrome 
    return n == reverse(n); 
  
  
# Function to calculate sum of all array 
# elements which are palindrome 
def sumOfArray(arr, n) : 
    s = 0; 
      
    for i in range(n) : 
        if ((arr[i] > 10) and isPalin(arr[i])) : 
          
            # summation of all palindrome numbers 
            # present in array 
            s += arr[i]; 
              
    return s; 
   
  
# Driver Code 
if __name__ == "__main__" : 
  
    n = 6; 
  
    arr = [ 12, 313, 11, 44, 9, 1 ]; 
  
    print(sumOfArray(arr, n)); 
     
    # This code is contributed by AnkitRai01 

Output:

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My Personal Notes

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

C++

Java

C#

Python3

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