Matrix

/**
 * @(#)matrixoperations.java
 *
 *Description: Fills 2 5x5 arrays with ranom values 1-100. Prints out the arrays, adds the arrays together and places the answer in a third array. Multiplies the first array by 2 and prints out the answer.
 *  		   Multiplies the 2nd array by 3 and displays the answer. Finally multiplys the first array by the second array and displays the answer in the third array.
 *
 * @author 
 * @version 1.00 2013/2/28
 */

import java.util.Random;
import java.util.Scanner;
public class matrix {


public static void populate(int MatrixA[][], int MatrixB[][], int MatrixC[][])
{
	    Random ranGen = new Random();
		for(int i=0;i<5; i++)
    	{
    		for(int x=0;x<5;x++)
    		{
    			MatrixA[i][x] = ranGen.nextInt(10)+1; //populates the first 2d array with numbers 1-100
    			MatrixB[i][x] = ranGen.nextInt(10)+1; //populates the second 2d array with numbers 1-100
    			MatrixC[i][x]=0;
    		}
    	}
}
public static void arrayOutput(int MatrixA[][], int MatrixB[][], int MatrixC[][]) //outputs the arrays as matrices
{
		Scanner textReader = new Scanner(System.in);
		System.out.println("Which array do you want to output? 1 for Matrix A, 2 for Matrix B, 3 for Matrix C");
		int choose = textReader.nextInt();
		switch(choose)
		{
		case 1:
		System.out.println("Matrix A");
    	for(int z=0;z<5; z++) //outputs Matrix A
    	{
    		System.out.println("");
    	for(int a=0;a<5;a++)
    		{
    			System.out.print(MatrixA[z][a]);
    			System.out.print(" ");
    		}
    	}
    	break;
    	case 2:
    	System.out.println("Matrix B"); //outputs Matrix B
    	for(int b=0;b<5; b++)
    	{
    		System.out.println("");
    	for(int r=0;r<5;r++)
    		{
    			System.out.print(MatrixB[b][r]);
    			System.out.print(" ");
    		}
    	}
    	break;
    	case 3:
    	System.out.println("Matrix C"); //outputs Matrix C
    	for(int b=0;b<5; b++)
    	{
    		System.out.println("");
    	for(int r=0;r<5;r++)
    		{
    			System.out.print(MatrixC[b][r]);
    			System.out.print(" ");
    		}
    	}
    	break;
		}
	
}

public static void addition(int MatrixA[][], int MatrixB[][], int MatrixC[][]) //adds the 2 matrices together and places them in Matrix C
{
	for(int i=0; i<5;i++)
	{
		for(int x = 0; x<5; x++)
		{
			MatrixC[i][x]=MatrixA[i][x] + MatrixB[i][x];
		}
	}
}


public static void multiplyA(int MatrixA[][]) //Multiplies Matrix A by 2
{
	for(int i=0; i<5; i++)
	{
		for(int x=0; x<5;x++)
		{
			MatrixA[i][x]=MatrixA[i][x]*2;
		}
	}
	System.out.println("Done");
}

public static void multiplyB(int MatrixB[][]) //Multiplies Matrix B by 3
{
		for(int i=0; i<5; i++)
	{
		for(int x=0; x<5;x++)
		{
			MatrixB[i][x]=MatrixB[i][x]*3;
		}
	}
}
public static void multiplyC(int MatrixA[][], int MatrixB[][], int MatrixC[][]) //Multiplies Matrix A by Matrix B and saves in Matrix C
{
	
	int i, x;
	//int add = 0;
	int sum=0;
		for(i=0;i<5;i++)
		{
			for(x=0;x<5;x++)
			{
				for(int z=0; z<5;z++)
				{
					
					sum+=(MatrixA[i][z]*MatrixB[z][i]);
					MatrixC[i][x] = sum;
					sum=0;
				}	
				
				
			}
			sum=0;
		}
}

public static void swap(int MatrixA[][],int MatrixC[][])
{
	for(int i=0; i<5;i++)
	{
		for(int x=0; x<5;x++)
		{
		}
	}
	MatrixA[0][0]=MatrixA[0][4];
	MatrixC[1][1]=MatrixA[1][3];
	MatrixC[2][2]=MatrixA[2][2];
	MatrixC[3][3]=MatrixA[1][1];
	MatrixC[4][4]=MatrixA[0][0];
}

    public static void main(String [] args)
    {
		Scanner textReader = new Scanner(System.in);
    	boolean run=true;
    	int[][] MatrixA = new int [5][5]; //creates a 2d array with 5 rows and 5 columns
    	int[][] MatrixB = new int [5][5]; //creates another 2d array with 5 rows and 5 columns
    	int[][] MatrixC = new int [5][5];
    	int option;
    	do{
    	System.out.println("\nPress 1 to populate the arrays.\nPress 2 to output the arrays.\nPress 3 to add MatrixA and MatrixB.\nPress 4 to Multiply Matrix A by 2.\nPress 5 to multiply MatrixB by 3.\nPress 6 to multiply Matrix A by Matrix B.\nPress 7 to swap the diagonals in MatrixA.\nPress 8 to exit the program.");
    	option =textReader.nextInt();
    	switch(option)
    	{
    	case 1:
    	populate(MatrixA, MatrixB, MatrixC);
    	break;
    	case 2:
    	arrayOutput(MatrixA, MatrixB, MatrixC);
    	break;
    	case 3:
    	addition(MatrixA, MatrixB, MatrixC);
    	break;
    	case 4:
    	multiplyA(MatrixA);
    	case 5:
    	multiplyB(MatrixB);
    	case 6:
    	multiplyC(MatrixA, MatrixB, MatrixC);
    	break;
    	case 7:
    	swap(MatrixA, MatrixC);
    	break;
    	case 8:
    	run=false;
    	break;	
    	}
    	}while(run==true);
    	
    	
    }
    
    
}