Double-Dimensional Arrays or 2d-Arrays

Arrays - 2D

Double-Dimensional Arrays or 2d-Arrays are the combination of rows and columns. Normally, a 2D-Array is use to represent data in the form of matrix.

Syntax to declare 2d-Arrays:

int a[3][4]; //3 rows and 4 columns

In the above syntax, 1st square bracket represents number of rows and 2nd square bracket represent number of columns. The above declaration tells the compiler that we are declaring 3 rows and 3 columns total 9 elements. We can specify any value in row and column.

Example 1: WAP to input 3x3 matrix and print it.

#include<stdio.h>
void main()
{
    int i, j, a[3][3];
    printf("Enter 3x3 matrix");
    for(i=0;i<=2;i++)
    {
        for(j=0;j<=2;j++)
            scanf("%d",&a[i][j]);
    }

    printf("Your 3x3 matrix is:\n");
    for(i=0;i<=2;i++)
    {
        for(j=0;j<=2;j++)
        {
            printf("\t%d",a[i][j]);
        }
        printf("\n");
    }
}

Initialization of 2D Array

int a[3][3] = {{10,20,30}, {40,50,60}, {70,80,90} };

Example 2: WAP to initialize the matrix.

#include<stdio.h>
void main()
{
	int a[3][3] = { {10,20,30}, {40,50,60}, {70,80,90} };
	int i, j;
	printf("\n3x3 Matrix is:\n");
	for(i=0;i<2;i++)
	{
		for(j=0;j<2;j++)
		{
			printf("%d  ",a[i][j]);
		}
		printf("\n");
	}
}