Java学习Day3
#进制问题
java中无法从静态上下文引用非静态变量
package lw; public class Transform { //进制问题 // public int a=15; public static void main(String[] args){ int i=10; // 10进制 int i1=010; // 8进制 int i2=0x10; //16进制 0-9 A-F System.out.println(i); System.out.println(i1); System.out.println(i2); // System.out.println(a //浮点数 float f=0.1f; double d=0.1; System.out.print(f==d); } }
#switch 语句 熟悉Scanner和Ramdom以及System.in
package lw; public class Switch { public static void main(String[] args){ int n=1; switch (n){ case 0: System.out.println("hello,00"); case 1: System.out.println("hello,1100"); } } }
#猜数字游戏
package lw; import java.util.Scanner; import java.util.Random; public class Number_game { public static void game(){ // int ranNumber=(int)(Math.random()*100+1);//100可以任意改成需要的范围 Scanner scan=new Scanner(System.in); int ranNumber=new Random().nextInt(10); while(true) { System.out.println("请输入您猜的数字:"); int num=scan.nextInt(); if (num < ranNumber) { System.out.println("猜小了"); } else if (num > ranNumber) { System.out.println("猜大了"); } else { System.out.println("恭喜您猜对了"); System.out.println("游戏结束"); break; } } } public static void main(String[] args) { System.out.println("******************"); System.out.println("****1.play********"); System.out.println("****0.exit********"); System.out.println("******************"); Scanner scan=new Scanner(System.in); System.out.println("请输入您的操作:"); int i=scan.nextInt(); if(i==1) { game(); }else if(i==0){ System.out.println("bye"); }else{ System.out.println("请重新输入:"); } } }
#数组的两种定义方法
package lw; public class Array_list { public static void main(String[] args){ int[] arr=new int[4]; //定义法1 int[] arr1; //定义法2 arr1=new int[4]; int[] arr2={1,2,3,4}; for(int i=0;i<4;i++){ System.out.println(arr[i]); System.out.println(arr1[i]); } } }