[数据结构]八皇后问题 棋盘 java实现

/**
 * Created by tianhongyan on 18/4/7.
 */
public class EightQueenSettlement {

    public static final int MAX_COUNT = 8;
    public int settleCount;
    int chessBoard[][] = new int[MAX_COUNT][MAX_COUNT];

    public boolean check(int x, int y){
        if(y==0){
            return true;
        }
        for(int i=1; i <= y;  i++){
            //纵向上是否可以摆放
            if(chessBoard[x][y-i] == 1){
                return false;
            }
            //左上方是否可以摆放
            if(x-i >= 0 &&  y-i >=0  && chessBoard[x-i][y-i] == 1){
                return false;
            }
            //右上方是否可以摆放
            if(x+i < MAX_COUNT && y-i >= 0 && chessBoard[x+i][y-i] == 1){
                return false;
            }
        }
        return true;
    }

    public void settleQueen(int n){
        if(n >= MAX_COUNT){
            return ;
        }
        for(int i=0; i<MAX_COUNT; i++){
            for(int j=0;j<MAX_COUNT;j++){
                chessBoard[j][n] = 0;
            }
            if(n == MAX_COUNT-1){
                if(check(i,n)){
                    chessBoard[i][n] = 1;
                    settleCount++;
                    printChessBoard(settleCount);
                }
                if(i>= MAX_COUNT){
                    break;
                }
            }else {
                if (check(i,n)) {
                    chessBoard[i][n] = 1;
                    settleQueen(n + 1);
                }
            }
        }
    }

    public void printChessBoard(int settleCount){
        System.out.println("第 "+settleCount +"种");
        for(int i=0; i<MAX_COUNT; i++){
            for(int j=0; j<MAX_COUNT; j++){
                System.out.print(chessBoard[i][j]+" ");
            }
            System.out.println();
        }
        System.out.println("===============");
    }

    public static void main(String[] args){
        EightQueenSettlement eightQueen = new EightQueenSettlement();
        eightQueen.settleQueen(0);
    }
}