费氏搜索法

/**
 * http://www.caterpillar.onlyfun.net/Gossip/AlgorithmGossip/FibonacciSearch.htm
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2006</p>
 * <p>Company: </p>
 * @author not attributable
 * @version 1.0
 */

public class FibonacciSearch {
  public static int search(int[] number, int des) {
    int[] fib = createFibonacci(number.length);
    int x = findX(fib, number.length + 1, des);
    int m = number.length - fib[x];
    x--;
    int i = x;
    if (number[i] < des)
      i += m;
    while (fib[x] > 0) {
      if (number[i] < des)
        i += fib[--x];
      else if (number[i] > des)
        i -= fib[--x];
      else
        return i;
    }
    return -1;
  }

  private static int[] createFibonacci(int max) {
    int[] fib = new int[max];
    for (int i = 0; i < fib.length; i++) {
      fib[i] = Integer.MIN_VALUE;
    }
    fib[0] = 0;
    fib[1] = 1;
    for (int i = 2; i < max; i++)
      fib[i] = fib[i - 1] + fib[i - 2];
    return fib;
  }

  private static int findX(int[] fib, int n, int des) {
    int i = 0;
    while (fib[i] <= n)
      i++;
    i--;
    return i;
  }

  public static void main(String[] args) {
    int[] number = {
        1, 4, 2, 6, 7, 3, 9, 8};
    QuickSort.sort(number);
    int find = FibonacciSearch.search(number, 3);
    if (find != -1)
      System.out.println("找到數值於索引" + find);
    else
      System.out.println("找不到數值");
  }
}