java新手问题求助

答案:2 悬赏:50

解决时间 2021-04-27 23:15

提问者网友：生亦何欢
2021-04-27 18:48

关于字符串的应用

以下是我写了一点点的代码一个计算器用代参的方法帮我写完下面的代码

import java.util.*;
public class ddd {
public static void main(String[] args){
Scanner input=new Scanner(System.in);
     int x;
         System.out.println("输入第一个数:");
          int a=input.nextInt();
         System.out.println("输入第二个数:");
          int b=input.nextInt();
          System.out.println("输入运算符:");
          String c=input.next();
}
}

最佳答案

二级知识专家网友：兮沫♡晨曦
2021-04-27 20:03

import java.util.*;
public class HelloAccp{
public static void main(String[] args){
  Scanner input = new Scanner(System.in);
  nn q = new nn();
  mm w = new mm();
  dd e = new dd();
  ww r = new ww();
  vv t = new vv();
  System.out.println("请输入第一个操作数：");
  int d = input.nextInt();
  System.out.println("请输入第二个操作数:");
  int b = input.nextInt();
  double jia1 = q.jia(d,b);
  double jian1 = w.jian(d,b);
  double chen1 = e.chen(d,b);
  double chu1 = r.chu(d,b);
  double yu1 = t.yu(d, b);
  System.out.println("请输入运算符：");
  String c = input.next();
  if (c.equals("+")){
  System.out.println(d+"+"+b+"="+jia1);}
  else if (c.equals("-")){
   System.out.println(d+"-"+b+"="+jian1);
   }
  else if (c.equals("*")){
   System.out.println(d+"*"+b+"="+chen1);
   }
  else if (c.equals("/")){
   System.out.println(d+"/"+b+"="+chu1);
   }
  else if (c.equals("%")){
   System.out.println(d+"%"+b+"="+yu1);
  }
}
}
class nn{
public int jia(int i,int j){
  return i+j;
}
}
class mm{
  public int jian(int i,int j){
   return i-j;
  }
}
class dd{
  public int chen(int i,int j){
   return i*j;
  }
}
class ww{
  public int chu(int i,int j){
   return i/j;
  }
}
class vv{
public int yu(int i ,int j){
  return i%j;
}
}

全部回答

1楼网友：哥在撩妹请勿打扰
2021-04-27 20:13

import java.math.BigDecimal; import java.util.Scanner; public class YunSuan{ //默认除法运算精度 private static final int DEF_DIV_SCALE = 10; //这个类不能实例化 private YunSuan(){ } public static double add(double v1,double v2){ BigDecimal b1 = new BigDecimal(Double.toString(v1)); BigDecimal b2 = new BigDecimal(Double.toString(v2)); return b1.add(b2).doubleValue(); } public static double sub(double v1,double v2){ BigDecimal b1 = new BigDecimal(Double.toString(v1)); BigDecimal b2 = new BigDecimal(Double.toString(v2)); return b1.subtract(b2).doubleValue(); } public static double mul(double v1,double v2){ BigDecimal b1 = new BigDecimal(Double.toString(v1)); BigDecimal b2 = new BigDecimal(Double.toString(v2)); return b1.multiply(b2).doubleValue(); } public static double div(double v1,double v2){ return div(v1,v2,DEF_DIV_SCALE); } public static double div(double v1,double v2,int scale){ if(scale<0){ throw new IllegalArgumentException( "The scale must be a positive integer or zero"); } BigDecimal b1 = new BigDecimal(Double.toString(v1)); BigDecimal b2 = new BigDecimal(Double.toString(v2)); return b1.divide(b2,scale,BigDecimal.ROUND_HALF_UP).doubleValue(); } public static void main(String []args){ Scanner in = new Scanner(System.in); boolean falg = true ; while(falg){ System.out.println("请输入第一个数:"); double d1 = in.nextDouble(); System.out.println("请输入第二个数:"); double d2 = in.nextDouble(); System.out.println("请输入要进行的运算：1:加 2:减 3: 乘 4:除 5:退出"); int c = in.nextInt(); switch(c){ case 1: System.out.println(add(d1,d2)); break; case 2: System.out.println(sub(d1,d2)); break; case 3: System.out.println(mul(d1,d2)); break; case 4: System.out.println(div(d1,d2)); break; case 5: System.out.println("退出系统!"); falg = false ; System.exit(0); break; } } } }

我要举报

如以上回答内容为低俗、色情、不良、暴力、侵权、涉及违法等信息，可以点下面链接进行举报！

点此我要举报以上问答信息！