二分查找 基本思想
二分查找是基于有序表查询的一种查找算法，二分的是意思是每次缩小查找的范围来加快查找速度二分查找算法 java二分查找算法 java 查找算法_02_二分查找（附java和python语言的编程实现），前提是查找的数组一定的得是有序的
图解示例
编码提要
编码的过程中二分查找算法 java，注意向左向右递归时，相应参数的设定
java语言编程实现
<p><pre>package com.cc.searchcollection;
/**
- @Classname Code_02_BinarySearch
- @Description TODO
- @Date 2020/3/3 13:50
- @Created by dreamBreathing
*/
public class Code_02_BinarySearch {
public static void main(String[] args) {
int[] arr = {1, 3, 5, 7, 9, 12};
int resultIndex = binarySearch(arr, 0, arr.length-1, 7);
if (resultIndex != -1) {
System.out.println("找到啦，下标为" + resultIndex);
} else {
System.out.println("数组中没有目标数");
}
System.out.println(resultIndex);
}
public static int binarySearch(int[] arr, int left, int right, int targetVal) {
if (left > right) {
return -1;
}
int mid = (left + right) / 2;
int midVal = arr[mid];
if (targetVal > midVal) {//向右递归查找
return binarySearch(arr, mid + 1, right, targetVal);
} else if (targetVal right:
return -1
mid = (left + right) // 2
mid_value = tag_list[mid]
if target > mid_value:
return binary_search(tag_list, mid + 1, right, target)
elif target