软件工程个人作业03

1.设计思想：

在四则运算1的基础上，多加了几个要求，是否有乘除法可以通过不同的选择然随机生成符号的函数有时候生成两个数字对应加减，有时候生成四个数对应加减乘除；括号没有实现；数值范围通过一个函数实现(int)(Math.random()*(m-n+1)+n)生成n~m的数字；加减有无负数在减法出负数时输出提示语句；另外求余，即把参与运算的两个数都定义为int类型，比如a,b都为int，a/b=c,若不能整除，余数等于a-c*b。

2.

package 加减乘除;

import java.util.Random;
import java.util.Scanner;

class number{
    static int a;
    static int b;
    static int c;
    static int d;
    static char f;
    static int x;
    static int s;
    public static int rand(){
        int n = 0;
        Random ra =new Random();    
        int a=(int)(Math.random()*(s-x+1)+x);
        {n=a;}
        return n;
    }
    public static void zhen(){
        Random a1 =new Random();int a2=a1.nextInt(10)+1;
        Random b1 =new Random();int b2=b1.nextInt(10)+1; 
        Random c1 =new Random();int c2=c1.nextInt(10)+1;
        Random d1 =new Random();int d2=d1.nextInt(10)+1;     
        if(a2>=b2||c2>=d2){
            zhen();
        }
        else{
        a=a2;b=b2;
        c=c2;d=d2;;
        }        
    }
    public static int GCD(int a, int b) {
        int max = Math.max(a, b);
        int min = Math.min(a, b);
        if(min == 0)
        return max;
        return GCD(min, max % min);
        }
    public static char fuhao(){
        char n = 0;
        Random ra =new Random();    
        int c=ra.nextInt(100)+1;
        if(c>=0&&c<25){ n = '+';}
        if(c<50&&c>=25){ n = '-';}
        if(c>=50&&c<75){ n = '*';}
        if(c>=75&&c<100){ n = '/';}    
        return n;        
    }  
     public static void zhengshow(){  
         a=rand();b=rand();f=fuhao();
         System.out.print(a);System.out.print(f);System.out.println(b+"=");
         double n = 0;
            if(f=='+'){
                n= a+b;
                System.out.println(n);
                System.out.println("");
            }
            if(f=='-'){
                n= a-b;
                System.out.println(n);
                System.out.println("");
                
            }
            if(f=='*'){
                n= a*b;
                System.out.println(n);
                System.out.println("");
            }
            if(f=='/'){
                int g = GCD(a,b);
                 System.out.println(a/g+"/"+b/g);
                 System.out.println("");
            }
            
     }
     public static void zhengwufushu(){  
         a=rand();b=rand();f=fuhao();
         System.out.print(a);System.out.print(f);System.out.println(b+"=");
         double n = 0;
            if(f=='+'){
                n= a+b;
                System.out.println(n);
                System.out.println("");
            }
            if(f=='-'){
                n= a-b;
                System.out.println(n);
                System.out.print("");
                if(n>0){
                    System.out.println("有负数");
                    zhengwufushu();
                }
            }
            if(f=='*'){
                n= a*b;
                System.out.println(n);
                System.out.println("");
            }
            if(f=='/'){
                int g = GCD(a,b);
                 System.out.println(a/g+"/"+b/g);
                 System.out.println("");
            }
            
     }
     public static void zhengwuyushu(){  
         a=rand();b=rand();f=fuhao();
         System.out.print(a);System.out.print(f);System.out.println(b+"=");
         double n = 0;
            if(f=='+'){
                n= a+b;
                System.out.println(n);
                System.out.println("");
            }
            if(f=='-'){
                n= a-b;
                System.out.println(n);
                System.out.println("");
                
            }
            if(f=='*'){
                n= a*b;
                System.out.println(n);
                System.out.println("");
            }
            if(f=='/'){
                int g = GCD(a,b);
                 System.out.println(a/g+"/"+b/g);
                 System.out.println("");
                 if((a<b&&g!=a)||(a>b&&g!=b)){
                     zhengwuyushu();
                 }
            }
            
     }
     public static void zhengwuchengchu(){      
            char f = fuhao();
            if(f!='*'&&f!='/')
            {
            a=rand();    b=rand();
            System.out.print(a);System.out.print(f);System.out.println(b+"=");
            double n = 0;
            if(f=='+'){
                n= a+b;
            }
            if(f=='-'){
                n= a-b;
                
            }

            System.out.println(n);
            System.out.println("");
            }
            else{
                zhengwuchengchu();
            }
        }
     public static void zhengwuchengchufushu(){      
            char f = fuhao();
            if(f!='*'&&f!='/')
            {
            a=rand();    b=rand();
            System.out.print(a);System.out.print(f);System.out.println(b+"=");
            double n = 0;
            if(f=='+'){
                n= a+b;
            }
            if(f=='-'){
                n= a-b;
                if(n<0){
                    System.out.println("有负数");
                    zhengwuchengchufushu();
                }
            }

            System.out.println(n);
            System.out.println("");
            }
            else{
                zhengwuchengchufushu();
            }
        }
     public static void zhenshow(){  
        zhen();f=fuhao();

         System.out.print("("+a+"/"+b+")");System.out.print(f);System.out.println("("+c+"/"+d+")"+"=");
        
         double n = 0;
            if(f=='+'){
                int g = GCD(((a*d)+(b*c)),(b*d));
                 System.out.println(((a*d)+(b*c))/g+"/"+(b*d)/g);
                 System.out.println("");
            }
            if(f=='-'){
                if((a*d)==(b*c)){
                    System.out.println("0");
                     System.out.println("");
                }
                else{
                int g = GCD(Math.abs(((a*d)-(b*c))),(b*d));
                 System.out.println(((a*d)-(b*c))/g+"/"+(b*d)/g);
                 System.out.println("");
                }
            }
            if(f=='*'){
                 int g = GCD((a*c),(b*d));
                 System.out.println((a*c)/g+"/"+(b*d)/g);
                 System.out.println("");
            }
            if(f=='/'){
    
                 int g = GCD((a*d),(b*c));
                 System.out.println((a*d)/g+"/"+(b*c)/g);
                 System.out.println("");
            }
            
     }
     public static void zhenwuchengchu(){  
            zhen();f=fuhao();
            if(f!='*'&&f!='/')
            {
             System.out.print("("+a+"/"+b+")");System.out.print(f);System.out.println("("+c+"/"+d+")"+"=");
            
             double n = 0;
             if(f=='+'){
                    int g = GCD(((a*d)+(b*c)),(b*d));
                     System.out.println(((a*d)+(b*c))/g+"/"+(b*d)/g);
                     System.out.println("");
                }
                if(f=='-'){
                    if((a*d)==(b*c)){
                        System.out.println(0);
                         System.out.println("");
                    }
                    else{
                    int g = GCD(Math.abs(((a*d)-(b*c))),(b*d));
                     System.out.println(((a*d)-(b*c))/g+"/"+(b*d)/g);
                     System.out.println("");
                    }
                }
                
                }
            else{
                zhenwuchengchu();
                
            }
         }
     public static void fanwei(){
            Scanner in = new Scanner(System.in);
            System.out.println("请输入式子的上限：");
            number.s=in.nextInt();
            System.out.println("请输入式子的下限：");
            number.x=in.nextInt();
     }
    
     }

public class Updata {
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        System.out.println("请输入显示式子的个数：");
        int m = in.nextInt();
        System.out.println("1.式子只有整数");
        System.out.println("2.式子只有真分数");
        System.out.println("请输入要执行的操作：");
        String[] strArray=new String[m];
         int type = in.nextInt();
         int p=0;
        switch(type){
        case 1:{
            number.fanwei();
            System.out.println("是否有乘除法：(1有0没有)");
            int n = in.nextInt();
            if(n==1){
                System.out.println("是否有负数：(1有0没有)");
                int n1 = in.nextInt();
                if(n1==1){
            for(int i = 0;i<m;i++){
            number.zhengshow();    
            p++;
            System.out.println("第"+p+"道");
            }
                }
                if(n1==0){
                    for(int i = 0;i<m;i++){
                    number.zhengwufushu();    
                    
                    }
                        }
            }
            if(n==0){
                System.out.println("是否有负数：(1有0没有)");
                int n1 = in.nextInt();
                if(n1==1){
            for(int i = 0;i<m;i++){
            number.zhengwuchengchu();    
            
            }
                }
                if(n1==0){
                    for(int i = 0;i<m;i++){
                    number.zhengwuchengchufushu();    
                    
                    }
                        }
                }
            } break;
        
        case 2:{
            System.out.println("是否有乘除法：(1有0没有)");
            int n = in.nextInt();
            if(n==1){
            for(int i = 0;i<m;i++){
            
            number.zhenshow();    
            }
            }
            if(n==0){
                for(int i = 0;i<m;i++){
                
                number.zhenwuchengchu();    
            
                }
            
                }
            } break;
        
        
        }
    }
}

3.截图