How to Take Array Input in Java

Java does not provide any direct way to take array input. But we can take array input by using the method of the Scanner class. To take input of an array, we must ask the user about the length of the array. After that, we use a Java for loop to take the input from the user and the same for loop is also used for retrieving the elements from the array. We can take any primitive type as input and invoke the corresponding method of the primitive type to take input of elements of the array.

In this section, we are going to learn how to take single-dimensional and two-dimensional array input in Java.

One-dimensional array input in Java

One-dimensional array or single dimensional array contains only a row. We can declare single-dimensional array in the following way:

The above statement occupies the space of the specified size in the memory.

Where,

datatype: is the type of the elements that we want to enter in the array, like int, float, double, etc.

arrayName: is an identifier.

new: is a keyword that creates an instance in the memory.

size: is the length of the array.

Let's create a program that takes a single-dimensional array as input.

ArrayInputExample1.java

import java.util.Scanner;
public class ArrayInputExample1 
{
public static void main(String[] args) 
{
int n;
Scanner sc=new Scanner(System.in);
System.out.print("Enter the number of elements you want to store: ");
//reading the number of elements from the that we want to enter
n=sc.nextInt();
//creates an array in the memory of length 10
int[] array = new int[10];
System.out.println("Enter the elements of the array: ");
for(int i=0; i<n; i++)
{
//reading array elements from the user 
array[i]=sc.nextInt();
}
System.out.println("Array elements are: ");
// accessing array elements using the for loop
for (int i=0; i<n; i++) 
{
System.out.println(array[i]);
}
}
}

Output:

Two-dimensional array input in Java

A two-dimensional array is an array that contains elements in the form of rows and columns. It means we need both row and column to populate a two-dimensional array. Matrix is the best example of a 2D array. We can declare a two-dimensional array by using the following statement.

Where,

datatype: is the type of the elements that we want to enter in the array, like int, float, double, etc.

arrayName: is an identifier.

new: is a keyword that creates an instance in the memory.

m: is the number of rows.

n: is the number of columns.

Let's create a Java program that takes a two-dimensional array as input.

ArrayInputExample2.java

import java.util.Scanner; 
public class ArrayInputExample2
{ 
public static void main(String args[]) 
{ 
int m, n, i, j; 
Scanner sc=new Scanner(System.in); 
System.out.print("Enter the number of rows: "); 
//taking row as input
m = sc.nextInt(); 
System.out.print("Enter the number of columns: "); 
//taking column as input
n = sc.nextInt(); 
// Declaring the two-dimensional matrix 
int array[][] = new int[m][n]; 
// Read the matrix values 
System.out.println("Enter the elements of the array: "); 
//loop for row
for (i = 0; i < m; i++) 
//inner for loop for column
for (j = 0; j < n; j++) 
array[i][j] = sc.nextInt(); 
//accessing array elements 
System.out.println("Elements of the array are: "); 
for (i = 0; i < m; i++) 
{ 
for (j = 0; j < n; j++) 
//prints the array elements
System.out.print(array[i][j] + " "); 
//throws the cursor to the next line
System.out.println(); 
} 
} 
}

Output: