C++ Multidimensional Arrays

C++ Multidimensional Arrays

C++ Multidimensional Arrays: In this tutorial, we’ll find out about multi-dimensional arrays in C++. All the more explicitly, how to pronounce them, access them, and use them effectively in our program.

In C++, we can make an array of an array, known as a multidimensional array. For instance:

int x[3][4];

Here, x is a two-dimensional array. It can hold a maximum of 12 elements.

We can think of this array as a table with 3 rows and each row has 4 columns as shown below.

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Three-dimensional arrays also work in a similar way. For example:

float x[2][4][3];

This array x can hold a limit of 24 components.

We can discover all outnumber of components in the array essentially by multiplying its measurements:

2 x 4 x 3 = 24

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Multidimensional Array Initialization

Like a normal array, we can initialize a multidimensional array in more than one way.

1. Initialization of two-dimensional array

int test[2][3] = {2, 4, 5, 9, 0, 19};

The above technique isn’t preferred. A superior method to instate this array with similar array elements is given underneath:

int  test[2][3] = { {2, 4, 5}, {9, 0, 19}};

This array has 2 rows and 3 columns, which is why we have two rows of elements with 3 elements each.

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2. Initialization of three-dimensional array

int test[2][3][4] = {3, 4, 2, 3, 0, -3, 9, 11, 23, 12, 23, 
                 2, 13, 4, 56, 3, 5, 9, 3, 5, 5, 1, 4, 9};

This is not a good way of initializing a three-dimensional array. A better way to initialize this array is:

int test[2][3][4] = { 
                     { {3, 4, 2, 3}, {0, -3, 9, 11}, {23, 12, 23, 2} },
                     { {13, 4, 56, 3}, {5, 9, 3, 5}, {5, 1, 4, 9} }
                 };

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Example 1: Two Dimensional Array

// C++ Program to display all elements
// of an initialised two dimensional array

#include <iostream>
using namespace std;

int main() {
    int test[3][2] = {{2, -5},
                      {4, 0},
                      {9, 1}};

    // use of nested for loop
    // access rows of the array
    for (int i = 0; i < 3; ++i) {

        // access columns of the array
        for (int j = 0; j < 2; ++j) {
            cout << "test[" << i << "][" << j << "] = " << test[i][j] << endl;
        }
    }

    return 0;
}

Output

test[0][0] = 2
test[0][1] = -5
test[1][0] = 4
test[1][1] = 0
test[2][0] = 9
test[2][1] = 1

In the above example, we have introduced a two-dimensional int array named test that has 3 “lines” and 2 “segments”.

Here, we have used the settled for loop to show the cluster components.

the external circle from I = 0 to I = 2 access the lines of the exhibit

the internal circle from j = 0 to j = 1 access the segments of the array

Finally, we print the array elements in each iteration.

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Example 2: Taking Input for Two Dimensional Array

#include <iostream>
using namespace std;

int main() {
    int numbers[2][3];

    cout << "Enter 6 numbers: " << endl;

    // Storing user input in the array
    for (int i = 0; i < 2; ++i) {
        for (int j = 0; j < 3; ++j) {
            cin >> numbers[i][j];
        }
    }

    cout << "The numbers are: " << endl;

    //  Printing array elements
    for (int i = 0; i < 2; ++i) {
        for (int j = 0; j < 3; ++j) {
            cout << "numbers[" << i << "][" << j << "]: " << numbers[i][j] << endl;
        }
    }

    return 0;
}

Output

Enter 6 numbers: 
1
2
3
4
5
6
The numbers are:
numbers[0][0]: 1
numbers[0][1]: 2
numbers[0][2]: 3
numbers[1][0]: 4
numbers[1][1]: 5
numbers[1][2]: 6

Here, we have used a settled for loop to take the contribution of the 2d array. When all the info has been taken, we have used another settled for loop to print the array members.

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Example 3: Three Dimensional Array

// C++ Program to Store value entered by user in
// three dimensional array and display it.

#include <iostream>
using namespace std;

int main() {
    // This array can store upto 12 elements (2x3x2)
    int test[2][3][2] = {
                            {
                                {1, 2},
                                {3, 4},
                                {5, 6}
                            }, 
                            {
                                {7, 8}, 
                                {9, 10}, 
                                {11, 12}
                            }
                        };

    // Displaying the values with proper index.
    for (int i = 0; i < 2; ++i) {
        for (int j = 0; j < 3; ++j) {
            for (int k = 0; k < 2; ++k) {
                cout << "test[" << i << "][" << j << "][" << k << "] = " << test[i][j][k] << endl;
            }
        }
    }

    return 0;
}

Output

test[0][0][0] = 1
test[0][0][1] = 2
test[0][1][0] = 3
test[0][1][1] = 4
test[0][2][0] = 5
test[0][2][1] = 6
test[1][0][0] = 7
test[1][0][1] = 8
test[1][1][0] = 9
test[1][1][1] = 10
test[1][2][0] = 11
test[1][2][1] = 12

The fundamental concept of printing elements of a 3d array is like that of a 2d array.

However, since we are controlling 3 measurements, we use a settled for circle with 3 complete loops rather than only 2.

As should be obvious, the intricacy of the array increments exponentially with the expansion in measurements.

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Please feel free to give your comment if you face any difficulty here.

C++ Arrays & String