Sudoku generator loop | 易学教程

问题

I'm trying to make a sudoku generator so I can make into a sudoku game and I've encountered a problem... I have successfully made a method which checks a certain cell and whether the number in it repeats in the same row, column or 3x3 square it belongs to but I have a problem with generating the numbers randomly and filling them in. Basically first I fill the first line with random numbers from 1-9 which only appear once in the line. My question is, is it possible to fill cell after cell with random numbers which suit the numbers generized so far or should I fill line by line? Or maybe square by square? Because my loop seems to turn into an infinite loop. Here's the code:

  package test;

    import java.util.Random;

    public class Test {
        public static void main(String[] args) {
            int[][]test=new int[9][9];
            int[]prva=new int[]{1,2,3,4,5,6,7,8,9};
            zapolniPrvo(test,prva);//fills the first line of the table
            print(test);
            System.out.println();
            int y=1;
            int x=0;
            int rn=0;
            int a=1;
            for(int i=1;i<9;i++){
                for(int j=0;j<9;j++){
                    while(!razlicnostT(j,i,test)){
                        test[i][j]=(int)(Math.random()*9+1);
                    }
                }
            }
            print(test);
        }
        public static boolean razlicnostT(int y,int x,int[][]test){ //checks for same number in the line, row and square
            int vrstica=0;
            int kolona=0;
            int yy=(y/3)*3;
            int xx=(x/3)*3;
            int yyy=(y%3);
            int xxx=(x%3);
            int kvadrat=0;
            boolean razlicnost=false;
            for(int i=yy;i<=yyy;i++){
                for(int j=xx;j<=xxx;j++){
                    if(test[i][j]==test[y][x]){
                        kvadrat++;
                    }
                }
            }
            for(int i=0;i<x;i++){
                if(test[y][i]!=test[y][x]){
                    vrstica++;
                }
            }
            for(int i=0;i<y;i++){
                if(test[i][x]!=test[y][x]){
                    kolona++;
                }
            }
            if((vrstica==x) && (kolona==y)&&(test[y][x]!=0)&&(kvadrat!=1)){
                razlicnost=true;
            } else {
                razlicnost=false;
            }
            return razlicnost;
        }
        public static void zapolniPrvo(int[][]test,int[]prva){
            randomize(prva);
            for(int i=0;i<9;i++){
                test[0][i]=prva[i];
            }
        }
        public static void print(int[][]test){
            for(int i=0;i<test.length;i++){
                for(int j=0;j<test.length;j++){
                    System.out.print(test[i][j]+" ");
                }
                System.out.println();
            }
        }
        public static void randomize (int[]temp){
            Random rnd = new Random();
            for (int i = temp.length - 1; i > 0; i--){
                int index = rnd.nextInt(i + 1);
                int a = temp[index];
                temp[index] = temp[i];
                temp[i] = a;
            }
        }
    }

Note: razlicnostT returns true if the number appears only once in the row/column/3x3 square and test is the table

回答1:

From what i can see statement causing problem is this

if((vrstica==x) && (kolona==y)&&(test[y][x]!=0)&&(kvadrat!=1)){ razlicnost=true;

Since razlicnost is intitially set to be false this statement is obviously never true and that causes while(!razlicnostT(j,i,test) running infinite.

It is definitely error in application logic. Unfortunately I am not able to help you with this since your code

Is poorly formated
Uses different language
Uses awfull(or none) naming conventions (names like y,yy,xxx are nightmare of anyone reviewing your code in the future)

My advice is to rewrite this code to be more readable because fixing it may take even longer time

来源：https://stackoverflow.com/questions/23071689/sudoku-generator-loop

标签

java

generator

sudoku