What is wrong? I really don't get it.

Question about the task

Crossing the road blindly

Java Syntax, Level 4, Lesson 4

Under discussion

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.io.*; import java.util.Scanner; public class Solution { public static void main(String[] args) throws Exception { //write your code here Scanner sc = new Scanner (System.in); int t = sc.nextInt(); if ((t%5 >= 0 ) && (t % 5 < 3)) { System.out.println("green"); } else if ((t%5>=3) && (t%5<4)) { System.out.println("yellow"); } else if ((t % 5 >= 4 )&&(t % 5 < 5)) { System.out.println("red"); } } }

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Anonymous #10428383

Level 12 , Seattle, United States

20 March 2019, 06:06

a couple things more. don't use scanner. call method println just once. declare a local String variable and initialize it " ". to assign the light color.

Anonymous #10428383

Level 12 , Seattle, United States

20 March 2019, 06:03

go for the simple solution first. i did the same as you trying to catch all "real number" entered. didn't work. why? I guess their compiler/cast to verify your code is very limited. even if your code is 100% right its probably will not verify here, because CodeGym plugin tries to interpret your code syntax like a real java compiler, but its fail on more complicated logical expressions. So, don't get tilt. go for the simple solution to achieve it. like this : if (m < 3) if (m <4) else than show the light. :) *Learning how things didn't works is a learning too. In my opinion this course needs a lot of improvements, but we are not here to discuss that ( actually this is my last critic about it), we are here to get this till the end no matters how its goes. all right . take care. and keeping going.

John Kluse

Level 6 , Bountiful, United States

16 March 2019, 21:26

Nice! I'm really impressed by the comparison syntax you came up with. It is much more efficient that the way that I initially came up with.

Guadalupe Gagnon

Level 37 , Tampa, United States

6 February 2019, 15:08

I think the big problem you are having is you should be using a double as inputs can be in decimal, and int values are not able to store these. Style points: The last 'if' statement is not needed (can just be 'else'), and in the other two the first expression is superfluous.

jaime

Level 5 , Barcelona, Spain

6 February 2019, 15:25

That's it, thanks !