/**********************************************************************************************
 * @file MatrixMultiply.java
 * @brief this is a program that multiplies two matrices together
 * @author Elizabeth Dutton
 * @data October 17, 2019
 **********************************************************************************************/

import java.util.Scanner;
    public class MatrixMultiply {
        public static void main(String[] args) {
                Scanner keyboard = new Scanner(System.in); //allows me to use scanners from user
                System.out.println("Enter the number of rows and columns for the first matrix:");
                int matrixOneRow; //rows of first matrix
                int matrixOneColumn; //rows of second matrix
                matrixOneRow = keyboard.nextInt(); //gets rows from user
                matrixOneColumn = keyboard.nextInt(); //gets columns from user

            // variables for for loops
            int i;
            int j;
            int k;


            int[][] matrixOne = new int[matrixOneRow][matrixOneColumn]; //a matrix with the rows and columns from user
            System.out.println("Enter the elements of the first matrix:");
            for (i=0; i<matrixOneRow; i++){ //keeps it within the row
                for (j=0; j<matrixOneColumn; j++) { //keeps it within the column
                    matrixOne[i][j]= keyboard.nextInt(); // stores the matrix values from user
                }

            }

                System.out.println("Enter the number of rows and columns for the second matrix:");
                int matrixTwoRow; //rows of first matrix
                int matrixTwoColumn; // rows of second matrix
                matrixTwoRow = keyboard.nextInt(); //gets rows from user
                matrixTwoColumn = keyboard.nextInt(); //gets columns from user



            int[][] matrixTwo = new int[matrixTwoRow][matrixTwoColumn]; //a matrix with the rows and columns from user
            System.out.println("Enter the elements of the second matrix:");
            for (i=0; i<matrixTwoRow; i++){ //keeps it within the row
                for (j=0; j<matrixTwoColumn; j++) { //keeps it within the column
                    matrixTwo[i][j]= keyboard.nextInt(); //stores the matrix values from user
                }

            }

                //if the columns of the first matrix and the rows of the second matrix do not match, the program should not run
                if (matrixOneColumn != matrixTwoRow) {
                    System.out.println("Please restart and enter another matrix, these values cannot multiply");

                }

            int[][] finalMatrix = new int [matrixOneRow][matrixTwoColumn]; //combines the multiplied matrix

                    for(i=0; i<matrixOneRow; i++) { //keeps it within the first matrix rows
                        for (j=0; i<matrixTwoColumn; j++) { // keeps it within the second matrix columns
                            for (k=0; k<matrixOneColumn; k++){ //keeps the matrices in the right place
                               finalMatrix[i][j] = (matrixOneRow * matrixOneColumn) + finalMatrix[i][j] ; // multiplying rows and columns and adding it to the stored value

                            }
                            System.out.print(finalMatrix[i][j] + "\t"); //prints out matrix in a organized way
                            }
                        System.out.println(""); //goes to new line when first row is done
                        }

    /**   for( i=0; i<finalMatrix.length; i++){
                for (j=0; j<finalMatrix[i].length; j++) {
                    System.out.print(finalMatrix[i][j] + "\t"); //prints out matrix in a organized way

                }
              //  System.out.println(""); //goes to new line when first row is done
            }
     **/


                    }



        }





        //        }

// start with columns of first matrix = rows of second matrix
         //   resulting matrix is rows of first matrix by columns of second matrix
            // calculate down on first matrix times across second matrix
            //multiply column of the first matrix times every row of the second matrix
                    // 3x3 4x2 2x5 try all, make sure some dont work and its error

         //       }