// not fixed //incorrect sum of primary and secondary diagonal /** * Input an M x N array of integers. Compute the sum of each row, column and each diagonal. * Display the numbers in table form and the sum for each row, column and each diagonal. * Separate the IPO (input, process, output) and repeat the operation. */ import java.util.Scanner; public class Program { static Scanner scan = new Scanner(System.in); public static void main(String[] args) { final int ROWSIZE = 3; final int COLSIZE = 3; int[][] num = new int[ROWSIZE][COLSIZE]; int[] sum = new int[ROWSIZE]; char resp; do { //Input inputValues(num); //input method call computeSumRow(num, sum); printRow(num, sum); sum = new int[ROWSIZE]; //need to reset computeSumColumn(num, sum); printCol(num, sum); computeSumDia(num, sum); System.out.print("\nContinue [n-to exit]: "); resp = scan.next().charAt(0); } while (resp != 'n'); }//end of method main //Input Values of Column and Row public static void inputValues(int[][] num) { System.out.println("Input values"); for (int row = 0; row < num.length; row++) //num.length refers to the row size for (int col = 0; col < num[row].length; ++col) //num[row].length -- num of cols in the row num[row][col] = scan.nextInt(); } // Print Column Row public static void printRow(int[][] num, int[] sum) { System.out.println("\nArray values *Sum of Row*"); for (int row = 0; row < num.length; row++) { //num.length refers to the row size for (int col = 0; col < num[row].length; col++) //num[row].length -- num of cols in the row System.out.print(" " + num[row][col]); System.out.println(" " + "Sum row " + (row + 1) + ": " + sum[row]); //System.out.println (); } } // Print Column Sum public static void printCol(int[][] num, int[] sum) { System.out.println("\nArray values *Sum of Column*"); for (int row = 0; row < num.length; row++) { //num.length refers to the row size for (int col = 0; col < num[row].length; ++col) //num[row].length -- num of cols in the row System.out.print(" " + num[row][col]); System.out.println(" " + "Sum col " + (row + 1) + ": " + sum[row]); //System.out.println (); } }//end of printALL method //Compute Sum of Row public static void computeSumRow(int[][] num, int[] sum) { for (int row = 0; row < num.length; row++) { //num.length refers to the row size for (int col = 0; col < num[row].length; col++) //num[row].length -- num of cols in the row sum[row] = sum[row] + num[row][col]; } } //Compute Sum of Column private static void computeSumColumn(int[][] num, int[] sum) { for (int row = 0; row < num.length; row++) { //num.length refers to the row size for (int col = 0; col < num[row].length; ++col) //num[row].length -- num of cols in the row sum[row] = sum[row] + num[col][row]; } }//end of computeSum method public static void computeSumDia(int[][] num, int[] sum) { for (int row = 0; row < num.length; row++) { //num.length refers to the row size int Pd = 0, Sd = 0; int col; for (col = 0; col < num[row].length; col++) if (row == col) Pd += num[row][col]; // Condition for the secondary diagonal if ((row + col) == (num.length - 1)) Sd += num[row][col]; /* Print and display the sum of primary diagonal */ System.out.println(" " + "Sum of Principal Diagonal:" + Pd); // Print and display the sum of secondary diagonal System.out.println(" " + "Sum of Secondary Diagonal:" + Sd); } } }

JAVA: Sum of each row, column, and each diagonal in a Matrix