package array;

/**
 * 1) 数组的插入、删除、按照下标随机访问操作；
 * 2）数组中的数据是int类型的；
 *
 * Author: Zheng
 */
public class Array {
  private int data[];
  private int n;
  private int count;

  public Array(int capacity) {
    data = new int[capacity];
    n = capacity;
    count = 0;
  }

  public int find(int index) {
    if (index < 0 || index >= count ) return -1;
    return data[index];
  }

  public boolean delete(int index) {
    if (index < 0  || index >= count) return false;
    for(int i = index + 1; i < count; ++i) {
      data[i-1] = data[i];
    }
    --count;
    return true;
  }

  public boolean insert(int index, int value) {
    if (index < 0 || index >= count) return false;
    if (count == n) return false;

    for (int i = count - 1; i >= index; --i) {
      data[i+1] = data[i];
    }
    data[index] = value;
    ++count;
    return true;
  }

  public boolean insertToTail(int value) {
    if (count == n) return false;
    data[count++] = value;
    return true;
  }

  public void printAll() {
    for (int i = 0; i < count; ++i) {
      System.out.print(data[i] + " ");
    }
    System.out.println();
  }

}