简单井字游戏

package homework;

import java.util.ArrayList;
import java.util.Scanner;

public class 井字游戏{
    //构建棋盘
    static ArrayList bulidLine(int n){
        ArrayList line = new ArrayList();
        for(int i =0;i<2*n+1;i++)
            line.add("-");
        return line;
    }
    static ArrayList bulidBlanks(int n){
        ArrayList blanks= new ArrayList();
        for(int i=0;i<n;i++){
            blanks.add("|");
            blanks.add(" ");
        }
        blanks.add("|");
        return blanks;
    }
    static ArrayList bulidPlaste(int n){
        ArrayList plate = new ArrayList();
        for (int i =0;i<n;i++){
            plate.add(bulidLine(n));
            plate.add(bulidBlanks(n));
        }
        plate.add(bulidLine(n));
        return plate;
    }
    static void show(ArrayList plate){
        for (int i = 0;i<plate.size();i++){
            ArrayList row=(ArrayList)plate.get(i);
            for(int j=0;j<row.size();j++)
                System.out.print(row.get(j));
            System.out.println();
        }
    }
    //下棋
    static boolean drop(ArrayList plate,int r,int c,String piece) {
        r = 2 * r - 1;
        c = 2 * c - 1;
        ArrayList row = (ArrayList) plate.get(r);
        if (row.get(c) == " "){
            row.set(c, piece);
            return true;
        }
        return false;
    }
    //判定胜负
    public static boolean judge(ArrayList plate,int n,String piece){
        //判断行
        int r;
        int count;
        for(r=1;r<2*n+1;r+=2) {
            //判断行
            count=0;
            ArrayList row = (ArrayList) plate.get(r);
            for (int j = 1; j < 2 * n + 1; j += 2) {
                if (row.get(j) == piece) {
                    count += 1;
                    if (count == n)
                        return true;
                }
            }
        }
        //判断列
        for(int i=1;i<2*n+1;i+=2){
            count=0;
            ArrayList row=(ArrayList)plate.get(i);
            for(int j=1;j<2*n+1;j+=2) {
                if (row.get(j) == piece) {
                    count += 1;
                    if (count == n)
                        return true;
                }
            }
        }
        //判断捺
        for(int i=1;i<2*n+1;i+=2){
            count=0;
            ArrayList row=(ArrayList)plate.get(i);
            if (row.get(i)==piece){
                count+=1;
                if (count==n)
                    return true;
            }
        }
        //判断撇
        for (int i= 2*n-1;i>0;i-=2){
            count=0;
            ArrayList row=(ArrayList)plate.get(i);
            if(row.get(i)==piece){
                count+=1;
                if(count==n)
                    return true;
            }
        }

        return false;
    }

    public static void main(String[] args) {
        Scanner reader = new Scanner(System.in);
        System.out.println("输入棋盘阶数");
        int n=reader.nextInt();
        ArrayList plate= bulidPlaste(n);
        show(plate);
        String piece = "x";
        int s=0;
        while (true) {
            System.out.println("请输入落子的行号");
            int row = reader.nextInt();
            System.out.println("请输入落子的列号");
            int col = reader.nextInt();
            if (!drop(plate, row, col, piece)){
                System.out.println("该处已有棋子，重新落子");
                continue;
            }
            s++;
            if(s==n*n){
                if(judge(plate,n,piece)){
                    System.out.println(piece+" win");
                    break;
                }
                else
                    System.out.println("平局");
                break;
            }
            show(plate);

            if(judge(plate,n,piece)){
                System.out.println(piece+" win");
                break;
            }
            piece=piece=="x"?"o":"x";
        }
    }
}