Java 數獨判斷

import java.util.Scanner;

public class Sudoku{
    public static int array [][] = new int [9][9];
 
    public static boolean checkRow(int row){
        int sum = 0;
  
        for(int i = 0; i < array.length; i++){
            sum += array[row][i];
        }
  
        if( sum < 45 || sum > 45 ){
            return false;
        }
  
        return true;
    }
 
    public static boolean checkColumn(int column){
        int sum = 0;
  
        for(int i = 0; i < array.length; i++){
            sum += array[i][column];
        }
  
        if( sum < 45 || sum > 45 ){
            return false;
        }
  
        return true;
     }
 
     public static boolean checkLittlePalaceGrid(int box){
         int sum = 0;
         int row = (box / 3) * 3;
         int column = (box < 3) ? box*3 : (box < 6) ? (box - 3)*3 : (box - 6)*3;
  
         for(int i = 0; i < 3; i++){
             for(int j = 0; j < 3; j++){
                 sum += array[i + row][j + column];
             }
         }
  
         if( sum < 45 || sum > 45 ){
             return false;
         }
         return true;
     }

     public static void main(String[] args){
         Scanner sc = new Scanner(System.in);
         boolean row=true,column=true,lpg=true;
  
         while( sc.hasNext() ){
             for(int j = 0; j < 9; j++ ){
                 int a [] = {0,0,0,0,0,0,0,0,0};
                 for(int k = 0; k < 9; k++){
                     a[k] = sc.nextInt();
                 }
                 array[j] = a;
              }
   
              int i = 0;
              while(i < array.length){
                  row = checkRow(i);
                  column = checkColumn(i);
                  lpg = checkLittlePalaceGrid(i);
                  if(row == false || column == false || lpg == false){
                      System.out.println("no");
                      break;
                  }
   
                  if( i == array.length - 1 ){
                      System.out.println("yes");
                  }
                  i++;
              }
         }  
     }
}

題目