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2D Arrays in C

What is a 2d array ?

A 2D array in C is essentially an array of arrays. It's a data structure that represents tabular data or matrices. In memory, a 2D array is stored in a contiguous block of memory, where elements are arranged in rows and columns.

Syntax :

datatype arrayName[rows][columns];

Declaration :

To declare a 2D array, you specify the data type and the dimensions (rows and columns) within square brackets. For example : This declares a 3x3 matrix of integers named matrix.
int matrix[3][3];

Initialization :

You can initialize the elements of a 2D array when you declare it.For example : This initializes a 3x3 matrix with specific values.
int matrix[3][3] = { {1, 2, 3}, {4, 5, 6}, {7, 8, 9} };

Accessing Elements :

You access elements using row and column indices.For example : matrix[0][0] accesses the element in the first row and first column.
int element = matrix[rowIndex][columnIndex];

Examples :

C Code

													
                                                      
#include <stdio.h>
main() {
	int i,j;
    int matrix[3][3] = { {1, 2, 3}, {4, 5, 6}, {7, 8, 9} };
    printf("Matrix:\n");
    for ( i = 0; i < 3; i++) {
        for (j = 0; j < 3; j++) {
            printf("%d ", matrix[i][j]);
        }
        printf("\n");
    }
}
                                                       

													
												

Output :
Matrix:
1 2 3
4 5 6
7 8 9

C Code

													 # Write a program to perform Addition of Two Matrices using double dimensional array.
                                                      
#include <stdio.h>
main() {
	int i,j,n,m;
	printf("Enter the number of row and column=");
	scanf("%d %d",&n,&m);
	int a[n][m],b[n][m],sum[n][m];
	printf("Enter the 1st matrix=");
	for(i=0;i<n;i++)
	{
		for(j=0;j<n;j++)
		{
			scanf("%d",&a[i][j]);
		}
	}
	printf("Enter the values of 2nd matrix=");
	for(i=0;i<n;i++)
	{
		for(j=0;j<m;j++)
		{
			scanf("%d",&b[i][j]);
		}
	}
	for(i=0;i<n;i++)
    {
    	for(j=0;j<m;j++)
    	{
    		sum[i][j]=a[i][j]+b[i][j];
		}
	}
	printf("The matrix after sum=\n");
	for(i=0;i<n;i++)
	{
		for(j=0;j<m;j++)
		{
		   printf("%d\t",sum[i][j]);
	    }
	    printf("\n");
	}
}
                                                       

													
												

Output :
Enter the number of row and column=2 2
Enter the 1st matrix=1 2 3 4
Enter the values of 2nd matrix=1 2 3 4
The matrix after sum=
2 4
6 8

C Code

													 # Write a program to interchange row and column elements of matrix i.e. transpose.
                                                      
#include<stdio.h>
main()
{
	int n,m,i,j;
	printf("Enter row & coloumn:");
	scanf("%d%d",&n,&m);
	int a[n][m];
	for(i=0; i<n; i++)
	{
		for(j=0; j<m; j++)
		{
			printf("Enter the value of matrix : ");
			scanf("%d",&a[i][j]);
		}
	}
	printf("Matrix after transpose : \n");
	for(i=0; i<n; i++)
	{
		for(j=0; j<m; j++)
		{
			printf("%d\t",a[j][i]);
		}
		printf("\n");
	}
	
}
                                                       

													
												

Output :
Enter row & coloumn:2 2
Enter the value of matrix : 1
Enter the value of matrix : 2
Enter the value of matrix : 3
Enter the value of matrix : 4
Matrix after transpose :
1 3
s 2 4

Importance of 2d array :

Two-dimensional arrays in C are important for a variety of reasons :
Representation of Matrices and Tables : 2D arrays are essential for representing matrices, grids, and tables.
Image Processing : In graphics and image processing, images are represented as 2D arrays where each element corresponds to a pixel.
Game Development : Many games use 2D arrays to represent game boards, maps, and levels. This structure is crucial for implementing game logic and rendering scenes.
Data Storage and Retrieval : 2D arrays facilitate the storage and retrieval of data in a structured manner. For example, in database management, data can be stored in a tabular form using 2D arrays.
Algorithm Implementation : Many algorithms, such as dynamic programming and graph traversal algorithms, rely on 2D arrays for storing intermediate results and maintaining state information.

Conclusion :

Understanding these fundamentals enables you to work effectively with 2D arrays in C, facilitating operations like matrix manipulations, image processing, and more.

2D Arrays in C

What is a 2d array ?

Syntax :

Declaration :

Initialization :

Accessing Elements :

Examples :

Importance of 2d array :

Conclusion :

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