TQC+ JAVA

JPA05.java

import java.util.Scanner;
public class JPA05 {
    public static Scanner keyboard = new Scanner(System.in);
    
    public static void main(String[] argv) {
        search();
        search();
    }
    
    public static void search() {
        int[] data = {5, 9, 13, 15, 17, 19, 25, 30, 45}; // 已排序資料

        System.out.print("請輸入要找尋的資料：");

        int target = keyboard.nextInt();
		int count = 0;
		boolean find = false;
		int num = data.length / 2;
		while(true) {
			count += 1;
			if(data[num] == target) {
				count -= 1;
				find = true;
				break;
			} else if(data[num] > target) {
				int index = 0;
				int end = 0;
				if(num % 2 == 0) {
					end = num * 2;
				} else {
					end = num * 2 + 1;
				}
				System.out.println("尋找區間：" + index + "(" + data[index] + ").." + (end) + "(" + data[end] + "),中間：" + num + "(" + data[num] + ")");
				if(num-1 < 0) {
					break;
				}
				if(num % 2 == 0) {
					num = (num-1) / 2;
				} else {
					num = num / 2;
				}
			} else {
				int mid = (data.length - 1 - num + 1);
				if(mid % 2 == 0) {
					mid = (mid-1) / 2;
				} else {
					mid = mid / 2;
				}
				if(count == 0) {
					System.out.println("尋找區間：" + 0 + "(" + data[0] + ").." + (data.length-1) + "(" + data[data.length-1] + "),中間：" + num + "(" + data[num] + ")");
				} else {
					System.out.println("尋找區間：" + (num+mid) + "(" + data[num+mid] + ").." + (data.length-1) + "(" + data[data.length-1] + "),中間：" + (num + mid) + "(" + data[num+mid] + ")");
				}
				if(num + 1 == data.length) {
					break;
				}
				num += 1;
			}
		}
		System.out.println("經過 " + count + " 次的尋找");
		if(find) {
			System.out.println("您要找的資料在陣列中第" + num + "個位置");
		} else {
			System.out.println(target + "不在陣列中");
		}
    }
}