/**
* @desc 二分查询（非递归方式）
* 案例：
* {1,3,8,10,11,67,100}，编程实现二分查找，要求使用非递归方式完成。
* @Author BUG汇总
*/
public class BinarySearchNonRecursive {
public static void main(String[] args) {
int[] arr = {1, 3, 8, 10, 11, 67, 100};
int index = binarySearch(arr, 1);
if (index != -1) {
System.out.println("找到了，下标为：" + index);
} else {
System.out.println("没有找到--");
}
}
private static int binarySearch(int[] arr, int target) {
int left = 0;
int right = arr.length - 1;
while (left <= right) {
int mid = (left + right) / 2;
if (arr[mid] == target) {
return mid;
} else if (arr[mid] > target) {
right = mid - 1; // 向左找
} else {
left = mid + 1; // 向右找
}
}
return -1;
}
}二分查找算法（非递归）
冬雷zz 2020-08-25 17:05
经测试，以下写法内存消耗会更少：
public int binarySearch(int[] nums, int target) {
int pivot, left = 0, right = nums.length - 1;
while (left <= right) {
pivot = left + (right - left) / 2;
if (nums[pivot] == target) return pivot;
if (target < nums[pivot]) right = pivot - 1;
else left = pivot + 1;
}
return -1;
}