Need help on counting

[nickels]

Well im writing a program in java and my program had to do with Sudoku but its only 4 by 4 not 9 by 9. My program checks to see weather the rows, columns, and regions add up to 10. The output would look like this...

Enter Row 1: 3 2 4 1
Enter Row 2: 4 1 3 2
Enter Row 3: 1 4 2 3
Enter Row 4: 2 3 1 4

REG-1:GOOD
REG-2:GOOD
REG-3:GOOD
REG-4:GOOD

ROW-1:GOOD
ROW-2:GOOD
ROW-3:GOOD
ROW-4:GOOD

COL-1:GOOD
COL-2:GOOD
COL-3:GOOD
COL-4:GOOD

SUDO:VALID

My problem is the last part where it says sudo:valid. I know i need to make a variable that counts the number of things that are invalid and if that variable's value is 0 at the end of the program then i have a valid sudoku. But im not sure how to do this. Anyone know how? Heres my code

import java.util.Scanner;

public class test
 {
public static void main( String args[] )
 {
Scanner input = new Scanner( System.in );
  int a1, a2, a3, a4, b1, b2, b3, b4, c1, c2, c3, c4, d1, d2, d3, d4;

System.out.print ( "Enter First Row:" ); 
 a1 = input.nextInt();  
 a2 = input.nextInt(); 
 a3 = input.nextInt();
 a4 = input.nextInt(); 

System.out.print ( "Enter Second Row:" ); 
 b1 = input.nextInt();  
 b2 = input.nextInt(); 
 b3 = input.nextInt();
 b4 = input.nextInt(); 

System.out.print ( "Enter Third Row:" ); 
 c1 = input.nextInt();  
 c2 = input.nextInt(); 
 c3 = input.nextInt();
 c4 = input.nextInt(); 

System.out.print ( "Enter Fourth Row:" ); 
 d1 = input.nextInt();  
 d2 = input.nextInt(); 
 d3 = input.nextInt();
 d4 = input.nextInt(); 

// Regions

if (a1 + a2 + b1 + b2 == 10)
 {
System.out.println ( "\nREG-1:GOOD" );
 }
else
 {
System.out.println ( "\nREG-1:BAD" );
 }

if (c1 + c2 + d1 + d2 == 10)
 {
System.out.println ( "REG-2:GOOD" );
 }
else
 {
System.out.println ( "REG-2:BAD" );
 }

if (a3 + a4 + b3 + b4 == 10)
 {
System.out.println ( "REG-3:GOOD" );
 }
else
 {
System.out.println ( "REG-3:BAD" );
 }

if (c3 + c4 + d3 + d4 == 10)
 {
System.out.println ( "REG-4:GOOD" );
 }
else
 {
System.out.println ( "REG-4:BAD" );
 }

// Rows

if (a1 + a2 + a3 + a4 == 10)
 {
System.out.println ( "\nROW-1:GOOD" );
 }
else
 {
System.out.println ( "\nROW-1:BAD" );
 }

if (b1 + b2 + b3 + b4 == 10)
 {
System.out.println ( "ROW-2:GOOD" );
 }
else
 {
System.out.println ( "ROW-2:BAD" );
 }

if (c1 + c2 + c3 + c4 == 10)
 {
System.out.println ( "ROW-3:GOOD" );
 }
else
 {
System.out.println ( "ROW-3:BAD" );
 }

if (d1 + d2 + d3 + d4 == 10)
 {
System.out.println ( "ROW-4:GOOD" );
 }
else
 {
System.out.println ( "ROW-4:BAD" );
 }


// comlumns

if (a1 + b1 + c1 + d1 == 10)
 {
System.out.println ( "\nCOL-1:GOOD" );
 }
else
 {
System.out.println ( "\nCOL-1:BAD" );
 }

if (a2 + b2 + c2 + d2 == 10)
 {
System.out.println ( "COL-2:GOOD" );
 }
else
 {
System.out.println ( "COL-2:BAD" );
 }

if (a3 + b3 + c3 + d3 == 10)
 {
System.out.println ( "COL-3:GOOD" );
 }
else
 {
System.out.println ( "COL-3:BAD" );
 }

if (a4 + b4 + c4 + d4 == 10)
 {
System.out.println ( "COL-4:GOOD" );
 }
else
 {
System.out.println ( "COL-4:BAD" );
 }


}

}

[r035198x]

Check an article in the Java howTos area by Jos which talks about sudoku solvers.

[ManidipSengupta]

Have you thought about using arrays? Here you go -

import java.util.Scanner; 
  
public class Sudoku4 { 
	protected	int	n=4, checkSum=10, failCount=0;
	protected	Scanner	input = new Scanner(System.in);

	public Sudoku4 () {
		int[][] a = new int[n][n];
		for (int iRow = 0 ; iRow < n ; iRow++) {
			System.out.print ( "Enter Row #"+(iRow+1)+ ": ");
			for (int jCol = 0 ; jCol < n ; jCol++)
				a[iRow][jCol] = input.nextInt();
		}

		// Regions
		System.out.println();
		int regionIndex = 1, xCount = n/2, yCount = n/2;
		for (int ix = 0 ; ix < n ; ix += xCount) {
			for (int jy = 0 ; jy < n ; jy += yCount) {
				failCount += checkRegion(a,
					ix, jy, xCount, yCount,
					"REG-" + regionIndex + ":");
				regionIndex++;
		}}

		// Rows
		System.out.println();
		regionIndex = 1; xCount = 1; yCount = n;
		for (int ix = 0 ; ix < n ; ix += xCount) {
			for (int jy = 0 ; jy < n ; jy += yCount) {
				failCount += checkRegion(a,
					ix, jy, xCount, yCount,
					"ROW-" + regionIndex + ":");
				regionIndex++;
		}}

		// Columns
		System.out.println();
		regionIndex = 1; xCount = n; yCount = 1;
		for (int ix = 0 ; ix < n ; ix += xCount) {
			for (int jy = 0 ; jy < n ; jy += yCount) {
				failCount += checkRegion(a,
					ix, jy, xCount, yCount,
					"COL-" + regionIndex + ":");
				regionIndex++;
		}}
                }

	private int checkRegion (int[][] a, int rowStart, int colStart,
			int rowCount, int colCount, String identifier) {
		int sum = 0, errCountInRegion = 1;
		for (int i = 0; i < rowCount ; i++)
			for (int j = 0 ; j < colCount ; j++)
				sum += a[i+rowStart][j+colStart];
		if (sum == checkSum)
			errCountInRegion = 0;
		System.out.println (identifier + 
			((errCountInRegion == 0) ? "GOOD" : "BAD"));
		return errCountInRegion;
	}

	public void printFailCount () {
		System.out.println();
		if (failCount == 0)
			System.out.println ("Sudoku: VALID");
		else
			System.out.println("Fail Count = " + failCount);
	}

	public static void main(String args[] ) { 
		new Sudoku4().printFailCount();
	}
}

I learnt about the Scanner class today, thanks to you. Best wishes, - M.

[moorcroft]

you could always just add a count variable at the top ie:

int failCount = 0;

Then each time it hits the code where it says

{
//if rows do not add to 10 output fail;
failCount++;
}

Then at the end, say

if failCount>0 output "Fail"