public class SortBinaryArray {
// Function to sort an array containing only 0s and 1s
public static void sortBinaryArray(int[] arr) {
int left = 0; // Index to track the left side
int right = arr.length - 1; // Index to track the right side
while (left < right) {
// If the left index is at 0, move it forward
if (arr[left] == 0) {
System.out.println("left: " + left);
left++;
}
// If the right index is at 1, move it backward
else if (arr[right] == 1) {
System.out.println("right: " + right);
right--;
}
// If left is 1 and right is 0, swap them
else {
int temp = arr[left];
arr[left] = arr[right];
arr[right] = temp;
System.out.println("swap() left: " + left + " right: " + right);
left++;
right--;
}
}
}
public static void main(String[] args) {
// Input: Binary array
int[] arr = {1, 0, 1, 0, 1, 0, 0, 1, 0};
// Sort the binary array
sortBinaryArray(arr);
// Output the sorted array
System.out.print("Sorted array: ");
for (int num : arr) {
System.out.print(num + " ");
}
}
}
/*
run:
swap() left: 0 right: 8
left: 1
right: 7
swap() left: 2 right: 6
left: 3
swap() left: 4 right: 5
Sorted array: 0 0 0 0 0 1 1 1 1
*/
