2020年实训之java基础
- java基础
- 1.简易计算器
- 2.利率
- 3.计算偶数的和
- 4.水仙花数
- 5.四的倍数
- 6.猜数字
- 7.循环嵌套
- 8.九九乘法表
- 9.break的使用continue的使用
- 10.素数
- 11.打印圣诞树
- 12.猴子吃桃
- 13.数组的使用
- 14.类和对象的使用
- 15.逆序输出
- 16.抓狐狸
- 17.冒泡排序
- 18.选择排序
- 19.二维数组
- 20.酒店门牌号分发
java基础
1.简易计算器
calculator();
2.利率
interest();
3.计算偶数的和
evenCount();
4.水仙花数
shuixianhuashu();
5.四的倍数
multipleOfFour();
6.猜数字
guessNum();
7.循环嵌套
countScore();
8.九九乘法表
nineNineMultiple();
9.break的使用continue的使用
useOfBreakAndContinue();
10.素数
sushu();
11.打印圣诞树
critsmersTree();
12.猴子吃桃
monkeyEatPeach();
13.数组的使用
useOfArray();
14.类和对象的使用
useOfStudent();
15.逆序输出
reserve();
16.抓狐狸
catchFox();
17.冒泡排序
maoPao();
18.选择排序
xuanZe();
19.二维数组
twoDimArray();
20.酒店门牌号分发
hotel();
package com.morning;
import java.util.Random;
import java.util.Scanner;
public class test1 {
public static void main(String[] args) {
// 1.简易计算器
// calculator();
// 2.利率
// interest();
// 3.计算偶数的和
// evenCount();
// 4.水仙花数
// shuixianhuashu();
// 5.四的倍数
// multipleOfFour();
// 6.猜数字
// guessNum();
// 7.循环嵌套
// countScore();
// 8.九九乘法表
// nineNineMultiple();
// 9.break的使用continue的使用
// useOfBreakAndContinue();
// 10.素数
// sushu();
// 11.打印圣诞树
// critsmersTree();
// 12.猴子吃桃
// monkeyEatPeach();
// 13.数组的使用
// useOfArray();
// 14.类和对象的使用
// useOfStudent();
// 15.逆序输出
// reserve();
// 16.抓狐狸
// catchFox();
// 17.冒泡排序
// maoPao();
// 18.选择排序
// xuanZe();
// 19.二维数组
// twoDimArray();
// 20.酒店门牌号分发
// hotel();
}
/**
* 酒店门牌号分发
*/
static void hotel() {
int[][] nums = new int[3][];
nums[0] = new int[] {101,102,103,104};
nums[1] = new int[] {201,202};
nums[2] = new int[] {301};
for(int i=0;i<nums.length;i++) {
for(int j=0;j<nums[i].length;j++) {
System.out.println(nums[i][j]);
}
}
}
/**
* 二维数组
*/
static void twoDimArray() {
int[][] arr = new int[][] {{1,2,6},{5,6,4}};
int row = arr.length;
int col = arr[0].length;
System.out.println(row+" "+col);
for(int i=0;i<row;i++) {
for(int j=0;j<col;j++) {
System.out.println(arr[i][j]);
}
}
}
/**
* 选择排序
*/
static void xuanZe() {
int[] nums = {2,3,5,7,1};
for(int i=0;i<nums.length;i++) {
for(int j=i+1;j<nums.length;j++) {
if(nums[i]>nums[j]) {
int temp = nums[i];
nums[i] = nums[j];
nums[j] = temp;
}
}
}
for(int i : nums) {
System.out.println(i);
}
}
/**
* 冒泡排序
* i : 0到length-1 [)
* j : 0到length-1-i [)
*/
static void maoPao() {
int[] maopao = new int[] {3,6,8,9,5,4};
for(int i=0;i<maopao.length-1;i++) {
for(int j=0;j<maopao.length-1-i;j++) {
if(maopao[j]>maopao[j+1]) {
int temp = maopao[j];
maopao[j] = maopao[j+1];
maopao[j+1] = temp;
}
}
}
for(int i : maopao) {
System.out.println(i);
}
}
/**
* 抓狐狸
*/
static void catchFox() {
int[] home = new int[5];
int position = (int)(Math.random()*5);
home[position] = 1;
Scanner scanner = new Scanner(System.in);
int i=1;
while(i<=5) {
System.out.println("狐狸现在"+position+"家中");
System.out.println("Please input your guessNum:");
int guess = scanner.nextInt();
if(guess<0||guess>4) {
System.out.println("Please input 0-4!次数-1!");
continue;
}
if(home[guess] == 1) {
System.out.println("bingo");
break;
}else {
System.out.println("go on");
home[position] = 0;
if(position == 0) {
position = 1;
home[position] = 1;
}else if(position == 4) {
position = 3;
home[position] = 1;
}else {
int[] moves = {-1,1};
//random()*2从0开始往下找两个值
int j = (int)Math.random()*2;
System.out.println("下标为:"+j);
int step = moves[j];
position += step;
home[position] = 1;
}
}
i++;
}
if(i > 5) {
System.out.println("游戏结束,请充值");
}
}
/**
* 逆序输出
* 交换数组元素位置并正序输出
*/
static void reserve() {
String[] languages = new String[] {"c","cpp","java","python","c#"};
for(int i=0;i<languages.length/2;i++) {
String temp = languages[i];
languages[i] = languages[languages.length-1-i];
languages[languages.length-1-i] = temp;
}
for(String string : languages) {
System.out.println(string);
}
}
/**
* 类和对象的使用
*/
static void useOfStudent() {
class Student{
int age;
double height;
void info() {
System.out.println(age+" "+height);
}
};
//定义一个Student类型的数组,名字叫student
//里面有两个元素
//元素类型为Student类型的类
Student[] student = new Student[2];
//分别给两个类开辟新空间
student[0] = new Student();
student[1] = new Student();
student[0].age = 5;
student[0].height = 5;
student[1].age = 6;
student[1].height = 6;
for(Student s : student) {
s.info();
}
}
/**
* 数组的使用
*/
static void useOfArray() {
//定义数组并静态初始化
int[] nums = new int[] {1,2,3};
//for循环遍历数组元素
//应是小于数组长度而非小队等于数组长度
for(int i=0;i<nums.length;i++) {
System.out.println(nums[i]);
}
double[] ds = new double[4];
//for each遍历数组元素
for(double d : ds) {
System.out.println(d);
}
}
/**
* 猴子吃桃
*/
static void monkeyEatPeach() {
int total = 1;
for(int i=2;i<=10;i++) {
total = (total+1)*2;
System.out.println("第"+(11-i)+"天还剩"+total);
}
System.out.println("总共摘了"+total);
}
/**
* 打印圣诞树
*/
static void critsmersTree() {
Scanner scanner =new Scanner(System.in);
System.out.println("Please input the tree's depth:");
int a = scanner.nextInt();
for(int i=1;i<=a;i++) {
for(int k=a;k>=i;k--) {
System.out.print(" ");
}
for(int j=1;j<=2*i-1;j++) {
System.out.print("*");
}
System.out.println("\n");
}
for(int i=0;i<=3;i++) {
for(int j=1;j<=(2*a-1)/2;j++) {
System.out.print(" ");
}
System.out.print("*");
System.out.println("\n");
}
}
/**
* 素数
*/
static void sushu() {
for(int i=2;i<100;i++) {
int temp=1;
for(int j=2;j<i;j++) {
if(i%j==0) {
temp=0;
break;
}
}
if(temp == 1) {
System.out.println(i+"This is a sushu");
}
}
}
/**
* break and continue的使用
*/
static void useOfBreakAndContinue() {
for(int i=1;i<=10;i++) {
if(i == 3) {
// break;
continue;
}
System.out.println(i);
}
}
/**
* 九九乘法表
*/
static void nineNineMultiple() {
for(int i=1;i<=9;i++) {
for(int j=1;j<=i;j++) {
System.out.print(j+"*"+i+"="+i*j+"\t");
}
System.out.print("\n");
}
}
/**
* 循环嵌套
*/
static void countScore() {
Scanner scanner = new Scanner(System.in);
for(int i=1;i<=3;i++) {
double sum = 0;
System.out.println("Please input the "+i+" class's score");
for(int j=1;j<=4;j++) {
System.out.println("Please input the "+j+" student's score:");
double score = scanner.nextDouble();
sum += score;
}
double avg = sum/4;
System.out.println("This class's avg score is:"+avg);
}
}
/**
* 猜数字
*/
static void guessNum() {
int a = (int)(Math.random()*100);
System.out.println("谜底:"+a);
Scanner scanner = new Scanner(System.in);
while(true) {
System.out.println("Please input your guessNum:");
int temp = scanner.nextInt();
if(temp == a) {
System.out.println("Congratulation");
}else {
System.out.println("Sorry");
continue;
}
}
}
/**
* 四的倍数
*/
static void multipleOfFour() {
int i = 0;
while(i<=100) {
if(i%4==0) {
System.out.println(i);
}
i++;
}
}
/**
* 水仙花数
*/
static void shuixianhuashu() {
System.out.println("Hi");
int i=100;
while(i<=999) {
int a = i/100;
int b = i/10%10;
int c = i%10;
if(i == Math.pow(a, 3)+Math.pow(b, 3)+Math.pow(c, 3)) {
System.out.println(i);
}
i++;
}
}
/**
* 计算偶数的和
*/
static void evenCount() {
int i=2;
int sum = 0;
while (i <= 100) {
sum += i;
i += 2;
}
System.out.println(sum);
}
/**
* 利率
*/
static void interest() {
double money = 1000.0;
double interestRate = 1.0175;
int years = 1;
while(years <= 10) {
money *= interestRate;
years++;
}
}
/**
* 简易计算器
*/
static void calculator() {
System.out.println("Please input two nums:");
Scanner scanner = new Scanner(System.in);
int a = scanner.nextInt();
int b = scanner.nextInt();
int result = 0;
System.out.println("please choose one way to count");
System.out.print("1.+\n2.-\n3.*\n4./\n");
int key = scanner.nextInt();
switch (key) {
case 1:
result = a+b;
break;
case 2:
result = a-b;
break;
case 3:
result = a*b;
break;
case 4:
if(b == 0)
break;
result = a/b;
default:
break;
}
System.out.println(result);
}
}