Java program to read and print a two-dimensional array :
In this tutorial, we will learn how to read elements of a two-dimensional array and print out the result. We will first read the row and column number from the user and then we will read all elements one by one using a loop.
Let’s take a look at the algorithm first :
Algorithm :
-
Read the row and column number first.
-
Create one two dimensional array to hold the numbers.
-
Using a for loop read all numbers and store it in the array.
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After the reading is completed, print out the numbers using an array.
Java program :
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
//1
int row, col;
//2
int arr[][];
//3
Scanner scanner = new Scanner(System.in);
//4
System.out.print("Enter the total number of row : ");
//5
row = scanner.nextInt();
//6
System.out.print("Enter the total number of column : ");
col = scanner.nextInt();
//7
arr = new int[row][col];
//8
for (int i = 0; i < row; i++) {
//9
for (int j = 0; j < col; j++) {
//10
System.out.print("Enter element for row = " + (i + 1) + " column = " + (j + 1) + " : ");
arr[i][j] = scanner.nextInt();
}
}
//11
System.out.println("You have entered the following array : ");
//12
for (int i = 0; i < row; i++) {
for (int j = 0; j < col; j++) {
System.out.print(arr[i][j] + " ");
}
System.out.println();
}
}
}
Explanation :
The commented numbers in the above program denote the step number below :
-
Create two variables to store the row and column numbers: row and col.
-
Create one two dimensional array arr[][] . The first [] denotes the row count and the second [] denotes column count.
-
Create one scanner object to read the user input values.
-
Ask the user to enter the row count.
-
Put the row count in row variable.
-
Similarly, ask the user to enter the column value and store it in the col variable.
-
Create one two dimensional array with row count as row and column count as col and assign it to the variable arr.
-
Start one for loop to run for row times.
-
Inside that loop, run one more loop and run it for col times.
-
Ask the user to enter one number and store it in [i][j] position. After both loops are completed, the array arr will hold all elements that user has entered.
-
Now, print out the entered array to the user.
-
Similarly, run two for loops and print out all numbers of arr.
Sample Output :
Enter the total number of row : 3
Enter the total number of column : 4
Enter element for row = 1 column = 1 : 1
Enter element for row = 1 column = 2 : 2
Enter element for row = 1 column = 3 : 3
Enter element for row = 1 column = 4 : 4
Enter element for row = 2 column = 1 : 5
Enter element for row = 2 column = 2 : 6
Enter element for row = 2 column = 3 : 7
Enter element for row = 2 column = 4 : 8
Enter element for row = 3 column = 1 : 9
Enter element for row = 3 column = 2 : 10
Enter element for row = 3 column = 3 : 11
Enter element for row = 3 column = 4 : 12
You have entered the following array :
1 2 3 4
5 6 7 8
9 10 11 12