2020-10-06

读入数据操作：

System.out.println(in.nextLine());

例如：输入英尺英寸，求身高。

import java.util.Scanner; public class Hello{ public static void main(String[] args){ int foot; int inch; Scanner in = new Scanner(System.in); foot = in.nextInt(); inch = in.nextInt(); System.out.println("foot="+foot+,"inch="+inch); System.out.println((foot+inch/12.0)*0.3048); } }

实现：

public static void main(String[] args) { int foot; int inch; Scanner in = new Scanner(System.in); System.out.println("请分别输入身高的英尺和尺寸，如输入/5 7/表示身高为5英尺，7英寸"); foot = in.nextInt(); inch = in.nextInt(); System.out.println("foot="+foot+",inch="+inch+";"); System.out.println((int)((foot+inch/12.0)*0.3048*100)+"cm"); for (int i = 1; i <= 9; i++) { for (int j = 1; j <= i; j++) { System.out.print(j + "*" + i + "=" + j * i + " "); } System.out.println(""); }

1`100求素数

int i,j; System.out.println("100以内的素数为："); a:for(i=2;i<100;i++){ for(j=2;j<i;j++) { if ((i%j)==0)break; } if (i==j) System.out.println(i+ " "); }

浮点数比较

{ double a =0.1; double b =0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1; System.out.println(a==b); System.out.println("a="+a+";b="+b); System.out.println(Math.abs(b-a) < 1e-6); }