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POerror while trying to get a sum
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copied!<p>I am trying to get the sum of my array called matrix. However when I compile it I receive this error: <code>bad operand types for binary operator '+' first type: int; second type:int[]</code>. I do not understand why this is causing an error. Please help me understand, here is my code:</p> <pre><code>/** Sophia Ali 1. Matrix, getSumMatrix, getSumMatrixDiag: Email just Matrix.java. Write a class called Matrix that contains a private 2-dimensional int array called 'matrix' that can be up to 10 rows by 10 columns maximum. Use two constants MAXROWS=10 and MAXCOLS=10 to construct 'matrix.' The Matrix class will also need the following attributes: private int rows; // number of rows to use in matrix private int cols; // number of cols to use in matrix The rows and cols will contains values that are less than equal to MAXROWS and MAXCOLS. Write a default Matrix class constructor that constructs the 'matrix' array with the following values: {{1,2,4,5},{6,7,8,9},{10,11,12,13}, {14,15,16,17}} The constructor must also set the rows and cols variables to match the above matrix. Write a method 'getSumMatrix' that returns the sum of all the integers in the array 'matrix'. Write a method 'getSumMatrixDiag' that returns the sum of all the integers in the major diagonal of the array 'matrix'. A major diagonal is the diagonal formed from the top left corner to the bottom right corner of the matrix. You do not have to write a TestMatrix class to test the Matrix class. Just use the BlueJ object creation and testing feature. */ public class Matrix { static final int MAXROWS = 10; static final int MAXCOLS = 10; private int rows; private int cols; private int [][] matrix = new int [MAXROWS][MAXCOLS]; public Matrix() { int matrix[][] = { {1, 2, 4, 5}, {6, 7, 8, 9}, {10, 11, 12, 13}, {14, 15, 16, 17}}; getSumMethod(matrix); getSumMatrixDiag(matrix); } public int getSumMethod(int[][] matrix) { int sum = 0; for (int i = 0; i < matrix.length; i++) { sum += matrix[i]; } return sum; } /* int i, result; result = 0; for(i=0; i < matrix.length; i++) { i++; result = result + i; } return result; } */ public int getSumMatrixDiag(int[][] matrix) { int sum = 0; for (int i =0; i< matrix.length; i++) { i++; sum = (int)(sum + matrix[i][i]); } return sum; } } </code></pre>

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