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Thread: Large number while adding arrays

  1. #1
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    Default Large number while adding arrays

    I am trying to add the arrays in the method anArray, but when i try to see the value, which should be 134/3 , it is returning "Their Test Sum = 33500" instead of the value of 134/3, why is it printing such a large number?


    public class FinalProject {
     
        /**
         * @param args the command line arguments
         */
        public static void main(String[] args)throws IOException {
            //Choice Of Options:
            //File I/O *
            //Arrays       
            //"String Class" Substr, CharAt etc.        
            int testScores = readFile();
            System.out.println("My Test Scores Avg: " + testScores);
            anArray();
        }
        public static int readFile () throws IOException {
            FileInputStream fstream = new FileInputStream("c:/scores.txt");
            DataInputStream in = new DataInputStream(fstream);
            BufferedReader br = new BufferedReader(new InputStreamReader(in));
            //Reading File
            String strLine;
            int myScores = 1;
            while ((strLine = br.readLine ()) != null) {
                myScores = Integer.parseInt(strLine);
                return myScores;
            }
            return myScores;
        }
        public static void anArray () {
            int[] hisTest;
            hisTest = new int [3];
            hisTest[0] = 33;
            hisTest[1] = 50;
            hisTest[2] = 51;
     
     
            System.out.println("Their Test Sum = " + hisTest[0] + hisTest[1]
                    + hisTest[2]/3);
        }
     
    }


  2. #2
    Super Moderator curmudgeon's Avatar
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    Default Re: Large number while adding arrays

    This does not look correct:

        public static int readFile () throws IOException {
            FileInputStream fstream = new FileInputStream("c:/scores.txt");
            DataInputStream in = new DataInputStream(fstream);
            BufferedReader br = new BufferedReader(new InputStreamReader(in));
            //Reading File
            String strLine;
            int myScores = 1;
            while ((strLine = br.readLine ()) != null) {
                myScores = Integer.parseInt(strLine);
                return myScores;
            }
            return myScores;
        }

    The code is guaranteed to return after reading one line given the return statement inside of the while loop. Why is that there?
    Also, consider putting in println statements to debug your code and to see what the program is actually reading in.

    Also curious: why are you using a FileInputStream and not a FileReader wrapped by the BufferedReader?

  3. #3
    Super Moderator Norm's Avatar
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    Default Re: Large number while adding arrays

    "Their Test Sum = 33500" instead of the value of 134/3,
    Did you copy that correctly? I get: Their Test Sum = 335017
    Here is what the code is doing: "33" + "50" + 51/3

    If you want the + to be an arithmetic operation vs String concatenation, wrap the expression in ()s
    If you don't understand my answer, don't ignore it, ask a question.

  4. The Following User Says Thank You to Norm For This Useful Post:

    curmudgeon (December 6th, 2012)

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