C Multi-Dimensional Arrays.

Multi Dimensional Array

     An array having more than one subscript or dimension is known as multi dimensional array.

                i.e.:  int arr[3][3]. 

Multi dimensional arrays are also known as arrays of arrays or matrix.

Syntax - Multi Dimensional Array

 In C, Multi-Dimensional arrays can be declared as follows:

Syntax:

Datatype  var_name[size1][size2][size3]......................[size n];

So, in the same way, we can declare the 2-D array as:

1. Two Dimensional array requires two subscript variables

2. In the following syntax size1 represents no of rows whereas size2 represents no of columns.

Syntax:

data-type varname [size1][size2];

          e.g. :    int c[2][4];

So, in the same way, we can declare the 3-D array as:

Syntax:

Datatype  var_name[size1][size2][size3];

        e.g. :    int c[2][3][4];

Two-dimensional array program :- 

Example 1: Sum of two matrices

// C program to find the sum of two matrices of order 2*2
#include <stdio.h>
Void main()
  {

  int  i,j;

   float a[2][2], b[2][2], result[2][2];
   // Taking input using nested for loop
    printf("Enter elements of 1st matrix\n");
    for ( i = 0; i < 2; ++i)
    for ( j = 0; j < 2; ++j)
     {
     printf("Enter a%d%d: ", i + 1, j + 1);
      scanf("%f", &a[i][j]);
      }
     
// Taking input using nested for loop
  printf("Enter elements of 2nd matrix\n");
   for (i = 0; i < 2; ++i)
    for ( j = 0; j < 2; ++j)
     {
     printf("Enter b%d%d: ", i + 1, j + 1);
      scanf("%f", &b[i][j]);
      }
      // adding corresponding elements of two arrays
       for (i = 0; i < 2; ++i)
        for (j = 0; j < 2; ++j)
        {
         result[i][j] = a[i][j] + b[i][j];
         }
         // Displaying the sum
          printf("\nSum Of Matrix\n");
          for ( i = 0; i < 2; ++i)
          for ( j = 0; j < 2; ++j)
          {
          printf("%.1f\t", result[i][j]);
           if (j == 1)
            printf("\n");
             } 
             }

OUTPUT :-

    Enter elements of 1st matrix

Enter a11: 1

Enter a12: 2

Enter a21: 3

Enter a22: 4

Enter elements of 2nd matrix

Enter b11: 2.2

Enter b12: 3

Enter b21: 3.5

Enter b22: 5

Sum Of Matrix

3.2     5.0

6.5     9.0

 Program File:(click the following .c file to get the program file)    

               Two-Dimensional-Array.c

Three-dimensional array program :-

Example 2: Three-dimensional array 

// C Program to store and print 12 values entered by the user
#include <stdio.h>
int main() {
int test[2][3][2];
int i,j,k;
printf("Enter 12 values: \n");
for ( i = 0; i < 2; ++i) {
for ( j = 0; j < 3; ++j) {
for ( k = 0; k < 2; ++k) {
  scanf("%d", &test[i][j][k]);
  }
  }
   }
   // Printing values with proper index.
    printf("\nDisplaying values:\n");
     for ( i = 0; i < 2; ++i) {
     for ( j = 0; j < 3; ++j) {
     for ( k = 0; k < 2; ++k) {
     printf("test[%d][%d][%d] = %d\n", i, j, k, test[i][j][k]);
      }
       }
        }
       }
        

OUTPUT:- 

Enter 12 values:

1 3 8 2 3 4 6 5 9 6 10 12

Displaying values:

test[0][0][0] = 1

test[0][0][1] = 3

test[0][1][0] = 8

test[0][1][1] = 2

test[0][2][0] = 3

test[0][2][1] = 4

test[1][0][0] = 6

test[1][0][1] = 5 

test[1][1][0] = 9

test[1][1][1] = 6

test[1][2][0] = 10

test[1][2][1] = 12

Program File:(click the following .c file to get the program file)    

         Three-Dimensional-Array.c