Java Recursion Method Is Not Working - Summing Elements In Array

Feb 2, 2015

I am trying to sum up the elements of an array. When I test my code the sum is always off by one. For example if I input: 20, 40,30 it gives me 89 instead of 90.

This is what I have so far:

public static void main(String[args]){
int size = kbd.nextInt();
int [] myArray = new int [size]
//user inputs the elements of array

[Code]....

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***** start code ***

public class AddArray {
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int sum = 0;
sum = addArray(myarray);
System.out.println(" hello");
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int myarray[] = new int [6];

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public static void displayOutputs (int[][] anArray) {
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This is my code and I get this as a result when I input 10,20,30,...,90 into array[0][0], array[0][1], ..., array[2][2] (3rows, 3columns array)

[[10, 20, 30], [40, 50, 60], [70, 80, 90]]

[[10, 20, 30], [40, 50, 60], [70, 80, 90]]

[[10, 20, 30], [40, 50, 60], [70, 80, 90]]

While I expect to get only

[10, 20, 30]

[40, 50, 60]

[70, 80, 90]

I get no errors at least when I have the same # of rows and # of columns. However, when I have more columns than rows, a compiler stops running when it runs columnSum method.Here's an error message.

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 2
at lab10.Array2DMethods.columnSum(Arrays2DDemo.java:70)
at lab10.Arrays2DDemo.main(Arrays2DDemo.java:111)
Java Result: 1

And here's my code

public static void columnSum (int[][] anArray) {
int sum =0;
for (int col=0; col < anArray.length; col++) {
sum=0;
for (int r = 0; r < anArray[col].length; r++ ){
sum += anArray[r][col];
}
System.out.println("Sum of column " + col + " = " + sum);
}
}

why my code doesn't work when I have more columns.

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This is what I have so far:

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* *
* * *
* * * *
* * *
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*
 
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[Code] ....
 
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*
* *
* * *
* * * *
Please enter an integer
*
* *
* * *
Please enter an integer
 
*
* *
* * *
* * * *
* * * * *
* * * * * *
* * * * * * *
* * * * * * * *
* * * * * * * * *
* * * * * * * * * *
* * * * * * * * * * *
* * * * * * * * * * * *
* * * * * * * * * * * * *
* * * * * * * * * * * * * *
* * * * * * * * * * * * * * *
Please enter an integer
Please enter an integer
 
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