Java Collection How to - Insert In Order method for array using binary search

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Question

We would like to know how to insert In Order method for array using binary search.

Answer

import java.util.Arrays;
//from  w w w .j  av a2  s. c o  m
public class Main {

  public static void main(String[] args) {
    insertInOrder(6);
    insertInOrder(17);
    insertInOrder(28);
    insertInOrder(-1);
    insertInOrder(19);
    insertInOrder(7);
    insertInOrder(12);

    System.out.println(Arrays.toString(array));

  }

  static int[] array = new int[20];
  static int target = -1;
  static int elements = 0;

  public static void insertInOrder(int n) {
    int pos = Arrays.binarySearch(array, 0, elements, n);
    if (pos < 0)
      pos = ~pos;
    if (pos < elements)
      System.arraycopy(array, pos, array, pos + 1, elements - pos);
    array[pos] = n;
    elements++;
  }
}

The code above generates the following result.

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