简单的二分查找
package lianxi; public class BinarySearch { public static int binarySearch(int[] array,int value) { int low = 0; int high = array.length -1; int middle; while (low <= high) { middle = (low + high)/2; if(array[middle] == value) { return middle; } if(value < array[middle]) { high = middle - 1; } if (value > middle) { low = middle + 1; } } return -1; } public static void main(String[] args) { int[] array = {1,2,34,56,67,78,89,100}; int index = 0; index = BinarySearch.binarySearch(array, 78); System.out.println(index); } }