Add two numbers represented by two arrays

// C# program to sum two numbers 
// represented two arrays.
using System;

class GFG {

    // Return sum of two number represented by 
    // the arrays. Size of a[] is greater than 
    // b[]. It is made sure be the wrapper 
    // function
    static int calSumUtil(int []a, int []b, 
                                int n, int m)
    {
        // array to store sum.
        int[] sum= new int[n];
    
        int i = n - 1, j = m - 1, k = n - 1;
    
        int carry = 0, s = 0;
    
        // Until we reach beginning of array.
        // we are comparing only for second 
        // array because we have already compare
        // the size of array in wrapper function.
        while (j >= 0) 
        {
            // find sum of corresponding element
            // of both array.
            s = a[i] + b[j] + carry;
            
            sum[k] = (s % 10);
    
            // Finding carry for next sum.
            carry = s / 10;
    
            k--;
            i--;
            j--;
        }
    
        // If second array size is less 
        // the first array size.
        while (i >= 0) 
        {
            // Add carry to first array elements.
            s = a[i] + carry;
            sum[k] = (s % 10);
            carry = s / 10;
    
            i--;
            k--;
        }
    
        int ans = 0;
    
        // If there is carry on adding 0 index 
        // elements append 1 to total sum.
        if (carry == 1)
            ans = 10;
    
        // Converting array into number.
        for ( i = 0; i <= n - 1; i++) {
            ans += sum[i];
            ans *= 10;
        }
    
        return ans / 10;
    }
    
    // Wrapper Function
    static int calSum(int []a, int []b, int n,
                                        int m)
    {
        // Making first array which have
        // greater number of element
        if (n >= m)
            return calSumUtil(a, b, n, m);
    
        else
            return calSumUtil(b, a, m, n);
    }
    
    // Driver program 
    public static void Main()
    {
        int []a = { 9, 3, 9 };
        int []b = { 6, 1 };
        
        int n = a.Length;
    
        int m = b.Length;
        Console.WriteLine(calSum(a, b, n, m));
    }
}

// This article is contributed by vt_m.

using System;
using System.Collections.Generic;

class Program
{
    static List<int> AddArrays(int[] arr1, int[] arr2, int n, int m)
    {
        // Initialize the result list to store the sum
        List<int> result = new List<int>();

        // Initialize the carry variable to 0
        int carry = 0;

        // Loop through the arrays from right to left
        for (int i = n - 1, j = m - 1; i >= 0 || j >= 0 || carry > 0; i--, j--)
        {
            // Calculate the sum of the corresponding digits in the arrays
            int sum = (i >= 0 ? arr1[i] : 0) + (j >= 0 ? arr2[j] : 0) + carry;

            // Calculate the carry, if any, to be added to the next sum
            carry = sum / 10;

            // Calculate the digit to be added to the result list
            int digit = sum % 10;

            // Add the digit to the result list
            result.Insert(0, digit);
        }

        // Return the result list
        return result;
    }

    static void Main()
    {
        // Initialize the input arrays
        int[] arr1 = { 9, 5, 4, 9 };
        int[] arr2 = { 2, 1, 4 };

        // Get the sizes of the arrays
        int n = arr1.Length;
        int m = arr2.Length;

        // Calculate the sum of the arrays and store it in the result list
        List<int> result = AddArrays(arr1, arr2, n, m);

        // Print the result list
        foreach (int digit in result)
        {
            Console.Write(digit);
        }
        Console.WriteLine();
    }
}