What is a 3-D array?

3-D arrays Coding examples 3-D array in C++3-D array in Java

1 min read

Aug 18, 2025

Arrays are used to store data and information on various data types. The greatest advantage of arrays is that they allow all data to be accessed in O(1) time complexity.

3-D arrays#

3-D arrays are referred to as multi-dimensional arrays. Multi-dimensional arrays are defined as an “array of arrays” that store data in a tabular form.

Imagine this, an array list of data elements makes a 1-D (one-dimensional) array. An array of 1-D arrays makes a 2-D (two-dimensional) array. Similarly, an array of 2-D arrays makes a 3-D ( three-dimensional) array.

A 3-D array can be declared as follows:

C++

#include <iostream>
using namespace std;
int main() {
 int arr[2][3][3] = 
    { 
        { {0,1,2}, {2,3,4}, {6,7,1} }, 
        { {6,7, 1}, {8,9, 2}, {9,14, 22} } 
    }; 
    // accessing a single value i.e 0
    cout << arr[0][0][0] << endl;
  
    // output each element's value by iterating through the array 
    for (int i = 0; i < 2; ++i) 
    { 
        for (int j = 0; j < 3; ++j) 
        { 
            for (int k = 0; k < 3; ++k) 
            {              
                cout << "Element at arr[" << i << "][" << j 
                     << "][" << k << "] = " << arr[i][j][k] 
                     << endl;
       
            } 
        }     
    } 
    return 0; 
}

Lines 5-9: We defined a 3-D array with the name of arr[] and it would have dimensions of $2\times3\times3$ and we have assigned values to its elements.
Line 12: We print the value of the element at the index [0][0][0] of the array arr.
Lines 15-27: This nested loop structure iterates through each element of the 3-dimensional array arr and prints out its indices along with its value.

After understanding 3-D array implementation in C++, it's time to understand that same example in Java.

3-D array in Java#

Click the "Run" button to execute the 3D array example below:

Java

class HelloWorld {
    public static void main( String args[] ) {
        
         int[][][] arr = { 
        { {0,1,2}, {2,3,4}, {6,7,1} }, 
        { {6,7, 1}, {8,9, 2}, {9,14, 22} } 
        };
        // accessing single value i.e 0
        System.out.println(arr[0][0][0]);
    // output each element's value by iterating through the array 
        for (int i = 0; i < 2; ++i) 
        { 
            for (int j = 0; j < 3; ++j) 
            { 
                for (int k = 0; k < 3; ++k) 
                { 
                
                    System.out.println("Element at arr[" + i + "][" + j
                        + "][" + k + "] = " + arr[i][j][k]);
            
                } 
            }         
        }          
    }
}

Written By:

Areeba Haider

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Table of Contents

What is a 3-D array?

3-D arrays#

Coding examples#

3-D array in C++#

3-D array in Java#

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