个人作业-四则运算题目生成程序

|博客班级|https://edu.cnblogs.com/campus/ahgc/AHPU-SE-19|
|作业要求|https://edu.cnblogs.com/campus/ahgc/AHPU-SE-19/homework/11376|
|作业目标|编写代码能够完成作业要求并且记录完成时间及各个事项|
| 学号 |3190704214|

代码如下：

package S1;
public class S2{
public static void main(String[] args) {
print30Questions();
}
private static void print30Questions() {
//说明：打印30道题函数，把接收到的题目字符串按照指定格式输出。
for (int i = 0; i < 10; i++) {
System.out.print( i+1 );
System.out.print("." + getPfQuestion() + " ");
System.out.print( i+11 );
System.out.print("." + getPfQuestion() + " ");
System.out.print( i+21 );
System.out.println("." + getPfQuestion());
}
}
private static String getPfQuestion() {
//说明：getPfQuestion()得到真分数题目函数，随机生成真分数题目，返回真分数题目字符串。
int t = 0;
String strz = "";

    int x1=1+(int)(Math.random()*10);
    int x2=1+(int)(Math.random()*10);//分母
    
    int y1=1+(int)(Math.random()*10);
    int y2=1+(int)(Math.random()*10);//分母
    
    if( x2 <= x1 ){
        t = x2;
        x2 = x1;
        x1 = t;
        if( x1 == x2 ) {
            x1 = x1 - 1;//保证分子比分母小
        }
    }
    
    if( y2 <= y1 ){
        t = y2;
        y2 = y1;
        y1 = t;
        if( y1 == y2 ) {
            y1 = y1 - 1;//保证分子比分母小
        }
    }
    
    int z=1+(int)(Math.random()*100);
    
    if( z<=25 ) {
        strz = "×";
    }
    if( z>25 && z<=50 ) {
        strz = "÷";
        if( y1 == 0 )
        y1 = y1 + 1;//除数的分子不能为0是不是
    }
    if( z>50 && z<=75) {
        strz = "+";    
    }
    if( z>75 ) {
        strz = "-";
        if( x1/x2 > y1/y2 ) {
            
            t = x1;
            x1 = y1;
            y1 = t;
            
            t = x2;
            x2 = y2;
            y2 = t;//保证减法是大数减去小数
        }
    }            
    
    String strx1 = String.valueOf( x1 );
    String strx2 = String.valueOf( x2 );
    String stry1 = String.valueOf( y1 );
    String stry2 = String.valueOf( y2 );

    String ques = " " + strx1 + "/" + strx2 + strz + stry1 + "/" + stry2 + "=";
        
    return ques;
}//getPfQuestion

}