Java: Move all 0's to the end of an array

Last update on December 21 2024 09:33:09 (UTC/GMT +8 hours)

Write a Java program to move all 0's to the end of an array. Maintain the relative order of the other (non-zero) array elements.

Pictorial Presentation:

Sample Solution:

Java Code:

// Import the java.util package to use utility classes, including Arrays.
import java.util.*;

// Define a class named Exercise26.
public class Exercise26 {
    // The main method for executing the program.
    public static void main(String[] args) throws Exception {
        // Declare and initialize an array of integers.
        int[] array_nums = {0, 0, 1, 0, 3, 0, 5, 0, 6};
        int i = 0;

        // Print the original array.
        System.out.print("\nOriginal array: \n");
        for (int n : array_nums)
            System.out.print(n + "  ");

        // Use a loop to move zeros to the end of the array.
        for (int j = 0, l = array_nums.length; j < l;) {
            if (array_nums[j] == 0)
                j++;
            else {
                // Swap the non-zero element with the first available zero.
                int temp = array_nums[i];
                array_nums[i] = array_nums[j];
                array_nums[j] = temp;
                i++;
                j++;
            }
        }

        // Fill the remaining positions with zeros.
        while (i < array_nums.length)
            array_nums[i++] = 0;

        // Print the array after moving zeros to the end.
        System.out.print("\nAfter moving 0's to the end of the array: \n");
        for (int n : array_nums)
            System.out.print(n + "  ");
        System.out.print("\n");
    }
}

Sample Output:

                                                                              
Original array:                                                        
0  0  1  0  3  0  5  0  6                                              
After moving 0's to the end of the array:                              
1  3  5  6  0  0  0  0  0 

Flowchart:

Java Code Editor:

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