[隨堂練習] TQC+510 二分搜尋法

import java.util.Scanner;
public class JPD05 {
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 high = data.length-1;
int low = 0;
int mid = 0;
int n = 0;
while(low <=high)
{
System.out.println("尋找區間:"+low+"("+data[low]+").."+high+"("+data[high]+")中間:"+mid+"("+data[mid]+")");
n++;
mid = (high+low)/2;
if(target>data[mid])
{
low = mid+1;
}
else if (target < data[mid])
{
high = mid-1;
}
else{
break;
}
}
System.out.println("經過"+n+"次尋找");
if(target == data[mid])
{
System.out.println("您要找的資料在陣列中的第"+mid+"的位置");
}
else{
System.out.println(target+"不在陣列當中");
}
}
}

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Rank: 1

2^#

蔡季樺發表於 2017-5-13 12:37 | 只看該作者

本帖最後由蔡季樺於 2017-8-20 15:14 編輯

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};
System.out.print("請輸入要找尋的資料：");
int target = keyboard.nextInt();
int high = data.length-1;
int low = 0;
int mid = 0;
int n = 0;
while(low <=high)
{
mid = (high+low)/2;
n++;
System.out.println("尋找區間:"+low+"("+data[low]+").."+high+"("+data[high]+")中間:"+mid+"("+data[mid]+")");
if(target>data[mid])
{
low = mid+1;
}
else if (target < data[mid])
{
high = mid-1;
}
else{
break;
}
}
System.out.println("經過"+n+"次尋找");
if(target == data[mid])
{
System.out.println("您要找的資料在陣列中的第"+mid+"個位置");
}
else{
System.out.println(target+"不在陣列當中");
}
}
}

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Rank: 1

3^#

蔡庭豪發表於 2017-5-13 12:41 | 只看該作者

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 high = data.length-1 ;
int low = 0;
int mid = 0;
int n = 0;
while(low<=high)
{
System.out.printf("尋找區間:%d(%d)..%d(%d),中間:%d(%d)",low,data[low],high,data[high],mid,data[mid]);
n++;
mid=(high+low)/2;
if(target>data[mid]){
low = mid+1;
}
else if(target<data[mid]){
high = mid-1;
}
else{
break;
}
}
System.out.println("經過"+n+"次的搜尋");
if(target == data[mid]){
System.out.println("您要找的資料在陣列中的第"+mid+"個位置");
}
else{
System.out.println(target+"不在陣列中");
}
}
}

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Rank: 1

4^#

王彥甯發表於 2017-5-13 12:42 | 只看該作者

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 high = data.length-1;
int low = 0;
int mid = 0;
int count = 0;
while(low<=high)
{
count++;
mid = (high+low)/2;
System.out.printf("尋找區間:%d(%d)..%d(%d),中間:%d(%d)\n",low,data[low],high,data[high],mid,data[mid]);
if(low<mid)
{
low=mid+1;
}
else if(high>mid)
{
high=mid-1;
}
else
{
break;
}
}
System.out.printf("經過%d次的尋找\n",count);
if(target==data[mid])
{
System.out.printf("您要找的資料在陣列中第%d個位置",mid);
}
else
{
System.out.printf("%d不在陣列中\n",target);
}
}
}

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