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Hi! If someone is more experienced than me please look at my code and help me figure it out what is going wrong. I mean code is working but I cannot pass the task. The "recommendation from the mentor" is "Be sure that the program works correctly for negative numbers". But I tried it with the negative numbers and it also works for me.

Write a program that:
1. reads a number N (must be greater than 0) from the console
2. reads N numbers from the console
3. Displays the maximum of the N entered numbers.

Requirements:

The program should read the numbers from the keyboard.
The program must display a number on the screen.
The class must have a public static void main method.
Don't add new methods to the Solution class.
The program should display the maximum of the N entered numbers.
The program should not display anything if N is less than or equal to 0.

package com.codegym.task.task05.task0532; import java.io.*; import static java.lang.Integer.MIN_VALUE; /* Task about algorithms */ public class Solution { public static void main(String[] args) throws Exception { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); int N = Integer.parseInt(reader.readLine()); int max = MIN_VALUE; //write your code here for(int i = 0; i < N; i++) { int N2 = Integer.parseInt(reader.readLine()); if (N2 > max) { max = N2; } } if(max >= 0) { System.out.println(max); } } }

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Guadalupe Gagnon

Level 37 , Tampa, United States

15 January 2020, 16:39

useful

The biggest problem with this code is that if N is greater than 0 then it should have an output, and no output otherwise. This code does not have output when max is less than or equal to 0, however negative numbers can be entered and the actual 'max' may be a negative. For example, lets say the user enters 5 for N, then enters these five numbers: -1, -2, -3, -4, -5 The maximum would be -1 and that should be output, but line 28 would return false because max would be less than 0 and no output would be activated. This and you need to fix line 16 as horst mentioned. Mihai Daniel Bone's tip is actually fairly decent as the Math.max(int, int) method is extremely fast, though you would need to adapt it to work with this code differently than what they use as an example.

Guadalupe Gagnon

Level 37 , Tampa, United States

15 January 2020, 16:47

solution

This is a rough draft of how the code should look/work:

public static void main(String[] args) throws IOException {
        // step 1: read in a value for N
        // step 2: check if N is greater than 0
        { // if step 2 is true then do these steps ↓, otherwise skip ahead
            // step 3: read in N numbers
            // step 4: determine max of the numbers from step 3
            // step 5: output the result of step 4
        }
    }

Adam Maichrzik

Level 22 , Katowice, Poland

15 January 2020, 19:34

Thank you so much. This was so helpful for me. I just remove the last command of if statement - "if(max >= 0)". And add this if statement which checks if N I grater than 0 as you recommend me to do. And I pass this task :)

hidden #10568956

Level 9

15 January 2020, 16:04

useful

i found this piece of art Math.Max(a,b) and you can make something like this.

int maximum = Math.max(Math.max(Math.max(a, b), Math.max(c, d)),Math.max(e,f));

horst

Level 26 , Not in list

14 January 2020, 22:42

Just a guess: In line 16, should it read Integer.MIN_VALUE instead of just MIN_VALUE? Does that make a difference? PS: Although your last condition seems to be passing: In line 28 you check for everything that is larger or equal to zero...