confusion about the ? operator

Question about the task

Under discussion

I have an idea for how the ? operator works: it is shorthand for if else statements. though I'm confused as to how it can be put as a return value of a method. At first, I thought the operator was syntactically equivalent (i.e. in any context, you can interchange the two and the program will yield the same output.) I try to test this by putting an if else statement as a return value, but I get an error. perhaps I'm not fully understanding the nature of return statements? personally, I learn how to code best when I have at least a very good idea of what the code is saying rather than "oh, it passed all the tests! I don't know how though!" any thoughts?

Write a function that computes the minimum of four numbers.
The function min(a, b, c, d) should use (call) the function min(a, b)

Hint:
You need to write the body of the two existing min functions.

Requirements:

The program should display text on the screen.
The min methods should not display text on the screen.
The main method should call min(a, b) and min(a, b, c, d).
The main method should display the result of the min methods. Each time, on a new line.
The min(a, b) method must return the minimum of the numbers a and b.
The min(a, b, c, d) method must use the min(a, b) method.
The min(a, b, c, d) method must return the minimum of the numbers a, b, c, and d.

package com.codegym.task.task02.task0217; /* Minimum of four numbers */ public class Solution { public static int min(int a, int b, int c, int d) { int m = 0; min(b, c) ? m = b : m = c; min(c, d) ? m = c : m = d; return m; public static int min(int a, int b) { return (a <= b) ? a : b; } public static void main(String[] args) throws Exception { System.out.println(min(-20, -10)); System.out.println(min(-20, -10, -30, -40)); System.out.println(min(-20, -10, -30, 40)); System.out.println(min(-40, -10, -30, 40)); } }

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Emeka

Level 4

25 April 2021, 01:10

thank you for the response, but I am still lost how the ternary operator like this public static int method(int variable){ //statement return int e1= 1 > 2 ? 3 : 4; } how come this does not work: public static int method(int variable){ //statement int e1; return if (1 > 2){ e1 = 3; }else{ e1 = 4; }; }

Guadalupe Gagnon

Level 37 , Tampa, United States

25 April 2021, 02:51

neither of those examples are valid code. if statements are used for program logic flow: if(condition) do something else do something else The ternary operator, while operating similar to an if-else statemen, is different in that it is used for setting a value. think of it as a conditional way of setting a value, so instead of something like this: String s = "duck"; you could have it set to one of two values based on a condition:

int i = 5;
String s = "duck" + (i > 0) ? "s" : "";

based on the result of the condtion the String sting could either be "duck" or "ducks". Try that code out and change i to 0 to see the difference. So, because of the differences between ternary being to set a value and if-else for logic control, you can imagine that you can't return logic flow, but you can return a value. On the other hand you can use logic flow to reach a return but you can't use a value to reach a return: Both of these will work just fine

//good examples:
if(/*condition*/) return value;
else return anotherValue;

return /*condition*/ ? /*value if true*/ : /*value if false*/;

while both of these will error out

// bad examples

return if(/*condition*/) /*.....*/
else /*...*/

/*condition*/ ? return /*...*/ : return /*...*/;

Gellert Varga

Level 23 , Szekesfehervar, Hungary

24 April 2021, 21:16

Try this program, it will explain how it is work:

public class MyClass {
    public static void main(String args[]) {
      int x=10;
      int y=25;
      int z = (x < y) ? 5 : 3;

      System.out.println(z);
    }
}

Read more about: https://www.geeksforgeeks.org/java-ternary-operator-with-examples/