sudoco.java

import java.util.Scanner;

public class sudoco {

    //Source: https://www.geeksforgeeks.org/how-to-print-colored-text-in-java-console/
    // Declaring ANSI_RESET so that we can reset the color
    public static final String ANSI_RESET = "\u001B[0m";
  
    // Declaring the color
    // Custom declaration
    public static final String ANSI_RED = "\u001B[31m";
    public static final String ANSI_BLUE = "\u001B[34m";
    public static final String ANSI_YELLOW = "\u001B[33m";
    public static final String ANSI_GREEN = "\u001B[32m";


    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        //initialze game board
        int[][] board = {
                {5,3,0, 0,7,0, 0,0,0},
                {6,0,0, 1,9,5, 0,0,0},
                {0,9,8, 0,0,0, 0,6,0},

                {8,0,0, 0,6,0, 0,0,3}, 
            
                {4,0,0, 8,0,3, 0,0,1},
                {7,0,0, 0,2,0, 0,0,6},

                {0,6,0, 0,0,0, 0,0,0},
                {0,0,0, 4,1,9, 0,0,5},
                {0,0,0, 0,8,0, 0,7,9}
            };
            /* easy board
            board[][] = {
                {5,3,0, 6,7,0, 0,1,0},
                {6,7,2, 1,9,5, 3,4,8},
                {1,9,8, 3,4,2, 0,6,0},

                {8,5,9, 7,6,1, 4,0,3}, 
                {4,2,0, 8,5,3, 0,9,1},
                {7,0,3, 0,2,0, 8,5,6},

                {0,6,1, 5,0,7, 2,8,4},
                {2,0,7, 4,1,9, 6,0,5},
                {3,4,5, 2,8,0, 1,7,9}
            };    
            */
        // Save Starting Board For Comparing
        int[][] iniboard = new int[9][9]; 
        for (int r = 0; r < 9; r++)
            for (int c = 0; c < 9; c++)
                iniboard[r][c] = board[r][c];
        //Loop Until Not Solved
        while (!is_solved(board)){
            //Print Board
            print(board, iniboard);
            //Input Index Where to Enter value
            int index;
            do{
                System.out.print("Input The Place(" + ANSI_YELLOW +"Row"+ ANSI_GREEN + "Coloum "+ ANSI_RESET + ") : ");
                index = input.nextInt();
            }while(!is_correct_index(iniboard, index(index)));
            //Input Value
            int value;    
            System.out.print("Enter Digit: ");
            value = input.nextInt();
            //If Wrong Value then Repeat
            if(!is_correct_value(board, index(index), value)){
                System.out.println();
                continue;
            }
            //Update value on index in board
            int r = index(index)[0];
            int c = index(index)[1];
            board[r][c] = value;
            System.out.println();
        }
        System.out.println("You Won");
        print(board, iniboard);
    }

    //Function To Print Board
    public static void print(int board[][], int iniboard[][]){
        //Header
        System.out.println(ANSI_GREEN + "    0  1  2     3  4  5     6  7  8" + ANSI_RESET);
        System.out.println("  ------------------------------------");
        //Table
        for (int i = 0; i < 9; i++){
            System.out.print(ANSI_YELLOW + i + ANSI_RESET+ " "  );
            System.out.print("|");
            for (int j = 0; j < 9; j++){
                //Red For Initisal System , Blue For User Input
                String colour =  ( (iniboard[i][j] != 0) ? ANSI_RED : ((board[i][j] != 0) ? ANSI_BLUE : "") ) ;
                System.out.print(" " + colour + board[i][j]+ ANSI_RESET + " ");
                if (j % 3 == 2)
                    System.out.print (" | ");
            }
            System.out.println("\b");
            if (i % 3 == 2)
                System.out.println("  ------------------------------------");
            
        }

        
    }
    // Value Validator
    public static boolean is_correct_value(int[][] board, int[] index, int value){
        //If wrong value
        if (value > 9 || value < 1){
            System.out.println("The Value Can be Only Between 1 - 9");
            return false;
        }
        int r = index[0];
        int c = index[1];
        //Coulum or Row Validator      
        for (int i = 0; i < 9; i++){
            if (board[r][i] == value ||  board[i][c] == value){
                System.out.println("Same Value Exsist In Colums or Row");
                return false;
            }
        }

        int center = box_centernum(r*10 + c);
        // Scan the Box for the repatation of value
        for (int i = -10; i < 20; i+=10){
            for (int j = -1; j < 2; j++){
                int x = center + i + j;
                int cr = index(x)[0];
                int cc = index(x)[1];
                if (board[cr][cc] == value){
                    //System.out.println("r: "+ cr +" C: " + cc + "center: " + center+ " value: " + value + " x: " + x);        
                    System.out.println("Same Value Exsist In the Box");
                    return false;
                }       
            }
        }
        // If All correct return true
        return true; 
    }
    //Validate Index
    public static boolean is_correct_index(int[][] board, int[] index){
        // Out of box?
        if (index[0] > 8 || index[1] > 8){
            System.out.println("Index is not On the Board");
            return false;
        }
        //If a inital value in input.
        if (board[index[0]][index[1]] != 0){
            System.out.println("The Value At Index Was Initize By System");
            System.out.println("You can only edit Which where 0 In Start");
            return false;
        }
        return true;
    }
    //Return Center Box Num.
    public static int box_centernum(int index){
        // If first row
        if (index < 3)
            return 11;
        if (index < 6)
            return 14;
        if (index < 9)
            return 17;
        // If First Coloum
        if (index % 10 == 0){
            if (index  < 30)
                return 11;
            else if (index < 60)
                return 42;
            else 
                return 72;
        }
        // Scan the adjecent Numbers
        for (int i = -10; i < 20; i+=10){
            for (int j = -1; j < 2; j++){
                int x = index + i + j;
                int r = index(x)[0];
                int c = index(x)[1];
                // If center box found return it.
                if (r % 3 == 1 && c % 3 == 1)
                    return x;        
            }
        }
        return -1;
    }
    //break the two digit index to seprate variable 
    public static int[] index(int index){
        int[] arr = new int[2];
        arr[1] = (index % 10) ;
        arr[0] = (index / 10) ;
        return arr;  
    }
    //Check if board is complete
    public static boolean is_solved(int[][] board){
        //if zero left means not complete
        for (int[] x: board){
            for (int y: x){
                if (y == 0){
                    return false;
                }
            }
        }
        return true;
    }

}