从最小到最大排序 3 个数字

Question

As part of a problem set I have to sort 3 numbers in ascending order. A simple enough task, but for some reason I'm not getting the expected result. Using arrays is not allowed. Below is my code; I've linked to my flowchart here . I cannot get the program to sort 3 numbers such as 5, 5, and -4. When I attempt that case, here is the output:

Enter three numbers.

In order -0.04 5.0 5.0In order 5.0 -0.04 5.0

If I get that one to work, I cannot get the case of 23, 0, 39 to sort. Not sure if I have over-complicated the attempt with so many cases; I feel that my flowchart covers all possibilities. Thanks in advance!

  import java.util.Scanner; 

class Main {
  public static void main(String[] args) {

    Scanner reader = new Scanner(System.in); 
    System.out.print("Enter three numbers.");

    double x = reader.nextDouble();
    double y = reader.nextDouble(); 
    double z = reader.nextDouble();

    if (x >= y){
            if (y >= z)
                System.out.print("In order " + z + " "+ y + " " + x);

            if  (z >= x)
                System.out.print("In order " + y + " "+ x + " " + z);

            if (x > z)
                System.out.print("In order " + y + " " + z + " " + x);
    }

    if (y > x)
    {
            if (z >= y)
                System.out.print("In order " + x + " " + y + " "+ z);
        if (z >= x)
            System.out.print("In order " + y + " " + x + " " + z);
        if (x > z)
            System.out.print("In order " + y + " " + z + " " + x);
    }


  }
}

Answer 1

You can solve this with no if (s) using Math.max(double, double) and Math.min(double, double) and basic addition and subtraction. Like,

double max = Math.max(x, Math.max(y, z));
double min = Math.min(x, Math.min(y, z));
double mid = x + y + z - max - min;
System.out.printf("In order %f %f %f%n", min, mid, max);

Using if and else comparisons instead of Math.max and Math.min is a little more complicated. Pick a default value and compare with the other two. Like,

double max = z;
if (x > max || y > max) {
    if (x > y) {
        max = x;
    } else {
        max = y;
    }
}
double min = z;
if (x < min || y < min) {
    if (x < y) {
        min = x;
    } else {
        min = y;
    }
}

double mid = x + y + z - max - min;
System.out.printf("In order %f %f %f%n", min, mid, max);

Answer 2

If you want to stick with the if/else logic, here's a slight modification to your original solution. Note the use of an else if. I have commented out your earlier lines of code for comparison.

import java.util.Scanner; 

class Main {
  public static void main(String[] args) {

    Scanner reader = new Scanner(System.in); 
    System.out.println("Enter three numbers.");  //Use println instead of print, that way the input begins on the next line

    double x = reader.nextDouble();
    double y = reader.nextDouble(); 
    double z = reader.nextDouble();

    if (x >= y){ //In the three responses below, y is always before x.  
            if (y >= z)
                System.out.print("In order " + z + " "+ y + " " + x);

            else if  (z >= x)
                System.out.print("In order " + y + " "+ x + " " + z);

            else if (x > z)
                System.out.print("In order " + y + " " + z + " " + x);
    }

    if (y > x){// In the three responses below, x is always before y
        if (z >= y)
            System.out.print("In order " + x + " " + y + " "+ z);
        else if (z >= x)
            //System.out.print("In order " + y + " " + x + " " + z); //In this case, z has to be smaller than y.  The order was off
            System.out.print("In order " + x + " " + z + " " + y);
        else if (x > z)
            //System.out.print("In order " + y + " " + z + " " + x);
            System.out.print("In order " + z + " " + x + " " + y); //Y is the biggest.  The order here was off.  
    }

  }
}

Answer 3

There is some issues with your if/else statements:

1. Use else if statements because either of the conditions will be true and not all and hence the result will be printed multiple times.
2. The second if statement the last two statements are wrong because if we enter that if statement then (x < y) for sure but you are printing x before y (now edited).

Here is the correct code:

if (x >= y) {
    if (y >= z)
        System.out.print("In order " + z + " " + y + " " + x);
    else if (z >= x)
        System.out.print("In order " + y + " " + x + " " + z);
    else if (x >= z)
        System.out.print("In order " + y + " " + z + " " + x);
} else {
    if (z >= y)
        System.out.print("In order " + x + " " + y + " " + z);
    else if (z >= x)
        System.out.print("In order " + x + " " + z + " " + y);
    else if (x >= z)
        System.out.print("In order " + z + " " + x + " " + y);
}

Answer 4

 import java.util.Scanner;

 public class a9 {
    public static void main(String[] args) {
    Scanner scan = new Scanner(System.in);
    
    System.out.println("Input your numbers !!");

    int a = scan.nextInt();
    int b = scan.nextInt();
    int c = scan.nextInt();


    var ok =  Math.min(a , Math.min(b , c)); 
     
    if ( ok == a ) {
        if (c > b ) {
           System.out.println("Your order is : " + "," + c + "," + b + "," + a);
        }
        else {
            System.out.println("Your order is : " + b + "," +  c + "," + a);
        }
    }
    else if (ok == b) {
        if( a > c) {
            System.out.println("Your order is : " + a + "," + c + "," + a);

        }
        else {
            System.out.println("Your order is : " + c + "," + a + "," + b);
        }
    }

    else {
        if ( b > a) {
            System.out.println("Your order is : " + a + "," +  b + "," + c);
        }
        else {
            System.out.println("Your order is : " + b + "," +  a + "," + c);
        }
    }
   

    
    
    
    
    scan.close();

}

}