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Midpoint sums Prob. 22" - I don't get the right answer because I don't understand what means "xxxxx.x" I think

I am trying to solve this exercise Problem 22 just for reinforcing my solving skills. I've already coded the answer. The task asks for "what is the sum of ALL the resulting y coordinates values? (Enter the number as a decimal in the form xxxxx.x (I dont understand what this means)) . My answers is 50616.0, but it is wrong. I hope you can help me. I don't know if I am doing wrong, or just I don't understand what the task means in the form xxxxx.x, I think it is decimal, no?

This is my code:

import java.io.*;
import java.math.BigDecimal;

public class Problema22 {

public static void main(String args[]) {
    File archivo = null;
    FileReader fr = null;
    BufferedReader br = null;


    try {
        archivo = new File("C:\\plane22.txt");
        fr = new FileReader(archivo);
        br = new BufferedReader(fr);
        String linea;
        int index = 0;
        int num = 0;
        String num2 = "";
        BigDecimal sol = BigDecimal.valueOf(0);

        while ((linea = br.readLine()) != null) //System.out.println(linea);
        {
            //System.out.println(linea);
            int line1 = linea.indexOf(",");
            int line2 = linea.lastIndexOf(",");
            int line3 = linea.indexOf("|");


            String y1 = linea.substring(line1+1, line3);
            String y2 = linea.substr开发者_开发技巧ing(line2+1, linea.length() );

            long sumys = (Integer.parseInt(y1)+ Integer.parseInt(y2))/2;

            sol = BigDecimal.valueOf(sumys).add(sol);
            //System.out.println(sol);





        }

        System.out.println(sol);

        //count((ArrayList<String>) arr);

    } catch (Exception e) {
        e.printStackTrace();

    }
}


They want the result in the form "xxxxx.x", meaning 5 digits before the dot and one after. Your answer is incorrect because it is an integer, while they want a floating point number.


I think your error is introduced in this line:

long sumys = (Integer.parseInt(y1)+ Integer.parseInt(y2))/2;

The /2 will truncate the .5 if the sum of the two Y coordinates is odd. As it is for this line:

170,509|341,54

You compute 281 for this one, but the midpoint's Y coordinate is 281.5.

I suggest parsing all the numbers into floating point variables and storing the intermediate results into floating point variables. A standard double should have the mantissa to accurately handle this data set.

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