二分法查找     时间复杂度为O(logn)   

public class BiSearch {  public static int search(int[] data, int find){int low = 0;

        int mid = 0;

        int upper = 0;if (null == data) {return -1;}

        upper = data.length - 1;while (low <= upper) {mid = (low + upper)/2;if (data[mid] > find) {upper = mid - 1;}else if (data[mid] < find) {low = mid + 1;}else {return mid;}}return -1;}public static void main(String[] args) {  int[] nums = { 55, 7, 28, -3, 1, 7, 29, 0, 5, 4 };  Bisearch.sort(nums, 10);  }  
}