# Add 2D Array In C#

## What is 2D Array(Matrix)?

Ans:- Matrix is a rectangular two-dimensional array of numbers arranged in rows and columns. A matrix with m rows and n columns can be called an m × n matrix. Individual entries in the matrix are called elements and can be represented by a[i,j] which suggests that the element a is present in the ith row and jth column.

Two matrices X and Y can be added if and only if they have the same dimensions that are, the same number of rows and columns. It is not possible to add a 2 × 3 matrix with a 3 × 2 matrix. The addition of two matrices can be performed by adding their corresponding elements as

(X+ Y)[i,j]= X[i,j] + Y[i,j]

## Algorithm

• Declare and initialize 2 two-dimensional arrays X and Y.
• Calculate the number of rows and columns present in the array X (as dimensions of both the arrays are the same) and store it in variables rows and cols respectively.
• Declare another array sum with similar dimensions.
• Loop through the arrays X and Y, add the corresponding elements
e.g x11 + y11 = sum11
•  Display the elements of array sum.
Solution
1. using System;
2.
3. namespace ConsoleMultipleClass
4. {
5.     class Program
6.     {
7.         static void Main(string[] args)
8.         {
9.             Program obj = new Program();
12.         }
13.
15.         {
16.             Console.Write("Enter Number to Define Rows & Column:- ");
18.
19.             int[,] array = new int[arrayLength, arrayLength];
20.             int[,] arraySecond = new int[arrayLength, arrayLength];
21.             int[,] arraySum = new int[arrayLength, arrayLength];
22.
23.             for (int i = 0; i < arrayLength; i++)
24.             {
25.                 for (int j = 0; j < arrayLength; j++)
26.                 {
27.                     Console.Write("Array Index [{0}][{1}]:- ",i,j);
29.                 }
30.             }
31.
32.             Console.WriteLine("---------------------------------------------------------------------");
33.             Console.WriteLine("This is Your First Array:-");
34.
35.             for (int i = 0; i < arrayLength; i++)
36.             {
37.                 for (int j = 0; j < arrayLength; j++)
38.                 {
39.                     if (j == 0)
40.                     {
41.                         Console.Write(array[i,j]);
42.                     }
43.                     else
44.                     {
45.                         Console.Write(" " + array[i,j]);
46.                     }
47.
48.                 }
49.                 Console.WriteLine();
50.             }
51.
52.             Console.WriteLine("---------------------------------------------------------------------");
53.             Console.WriteLine("Now Enter Your Second Array");
54.
55.             for (int i = 0; i < arrayLength; i++)
56.             {
57.                 for (int j = 0; j < arrayLength; j++)
58.                 {
59.                     Console.Write("Array Index [{0}][{1}]:- ", i, j);
61.                 }
62.             }
63.
64.             Console.WriteLine("---------------------------------------------------------------------");
65.             Console.WriteLine("This is Your Second Array:-");
66.
67.             for (int i = 0; i < arrayLength; i++)
68.             {
69.                 for (int j = 0; j < arrayLength; j++)
70.                 {
71.                     if (j == 0)
72.                     {
73.                         Console.Write(arraySecond[i, j]);
74.                     }
75.                     else
76.                     {
77.                         Console.Write(" " + arraySecond[i, j]);
78.                     }
79.
80.                 }
81.                 Console.WriteLine();
82.             }
83.
84.             Console.WriteLine("---------------------------------------------------------------------");
85.             Console.WriteLine("Do you want to add this arrays:- (Y/N)");
86.
88.
89.             if (userInput.ToUpper() == "Y")
90.             {
91.                 for (int i = 0; i < arrayLength; i++)
92.                 {
93.                     for (int j = 0; j < arrayLength; j++)
94.                     {
95.                         arraySum[i, j] = array[i, j] + arraySecond[i, j];
96.                     }
97.                 }
98.                 Console.WriteLine("---------------------------------------------------------------------");
99.                 Console.WriteLine("Array is Added Successfully Here is your Result");
100.                 Console.WriteLine("---------------------------------------------------------------------");
101.                 for (int i = 0; i < arrayLength; i++)
102.                 {
103.                     for (int j = 0; j < arrayLength; j++)
104.                     {
105.                         if (j == 0)
106.                         {
107.                             Console.Write(arraySum[i,j]);
108.                         }
109.                         else
110.                         {
111.                             Console.Write(" " + arraySum[i, j]);
112.                         }
113.
114.                     }
115.                     Console.WriteLine();
116.                 }
117.             }
118.             else
119.             {
120.                 Console.WriteLine("Program Terminate Press Enter To Exit............");
121.             }
122.         }
123.     }
124. }