用java实现折半查找

package service;

import java.util.Scanner;

public class Test003 {
public static int Max = 20;
// 数据数组源
public static int data[] = { 12, 16, 19, 22, 25, 32, 39, 39, 48, 55, 57,58,63, 68, 69, 70, 78, 84, 88, 90, 97 };
// 计数器
public static int count = 1;
public static void main(String[] args) {
System.out.println("请输入您要查找的数字：");
Scanner sc = new Scanner(System.in);
int KeyValue = sc.nextInt();
// 调用折半查找
if (Search(KeyValue)) {
// 输出查找次数
System.out.println("共查找了" + count + "次");
} else {
// 输出没有找到数据
System.out.println("抱歉,数据数组源中找不到您输入的数字");
}
}

// 折半查找法
public static boolean Search(int k) {
int left = 0;// 左边界变量
int right = Max - 1;// 右边界变量
int middle;// 中位数变量
while (left <= right) {
middle = (left + right) / 2;
if (k < data[middle]) {
right = middle - 1;// 查找前半段
} else if (k > data[middle]) {
left = middle + 1;// 查找后半段
} else if (k == data[middle]) {
System.out.println("Data[" + middle + "] = " + data[middle]);
return true;
}
count++;
}
return false;
}
}