java算法之折半查找

package althorgrim;/** * 1、必须采用顺序存储结果 * 2、关键字必须有序 * @author hanrk-2734 * */public class TestBinarySearch {public static int binarySearch(int a[],int goal){int high=a.length-1;int low=0;while (low<=high) {int middle=(low+high)/2;if (a[middle]==goal) {return middle;}else if (a[middle]>goal) {high=middle-1;}else {low=middle+1;}}return -1;}/** * @param args */public static void main(String[] args) {// TODO Auto-generated method stubint[] src = new int[] {1, 3, 5, 7, 8, 9};System.out.println(binarySearch(src, 3)); }}