comma input vs period input

Question about the task

Under discussion

Hm.. I can't make my code work with the input of "2.5", but it works for "2,5" - do you use the wrong data type for my scanner? I have tried float and long also.. what else can I do?

The pedestrian traffic light is programmed as follows:
at the beginning of each hour, the green signal is on for three minutes,
then the signal is yellow for one minute,
and then it is red for one minute.
Then the light is green again for three minutes, etc.
Use the keyboard to enter a real number t that represents the number of minutes that have elapsed since the beginning of the hour.
Determine what color the traffic light is at the specified time.
Display the result as follows:
"green" if the light is green,
"yellow" if the light is yellow, and
"red" if the light is red.

Example for 2.5:
green
Example for 3:
yellow
Example for 4:
red
Example for 5:
green

Requirements:

The program should read a real number from the keyboard.
The program should display text on the screen.
If the light is green, display: "green"
If the light is yellow, display: "yellow"
If the light is red, display: "red"

package com.codegym.task.task04.task0416; /* Crossing the road blindly */ import java.util.Scanner; public class Solution { public static void main(String[] args) throws Exception { Scanner sc = new Scanner(System.in); double t = sc.nextDouble(); if (t % 5 == 0) { System.out.println("green"); } if (t % 5 == 2) { System.out.println("yellow"); } if (t % 5 == 1 ) { System.out.println("red"); } } }

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horst

Level 26 , Not in list

20 October 2020, 12:24

In my opinion, it doesn't matter whether you use a fullstop or a comma - indeed, since you're not parsing a double, but explicitly reading one (nextDouble()), I am expecting an InputMismatchException (or something) if you try to run it with 2,5 instead of 2.5. The real reason why your code doesn't work is that 2.5 modulo 5 is still 2.5 and not 0 or 2 or 2.0 In my case, I explicitly typecasted the input to an integer, thereby "getting rid" of the decimal places, and afterwards check the result of this integer modulo 5. (Be aware that there are more possible results of "something mod 5" than just the three you are currently checking).