kob/backendCloud/botRunningSystem/src/main/java/com/kob/botRunningSystem/utils/Bot.java

package com.kob.botRunningSystem.utils;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Bot implements java.util.function.Supplier<Integer>{


    @Override
    public Integer get() {
        File file = new File("input.txt");
        try {
            Scanner sc = new Scanner(file);
            return nextMove(sc.next());
        } catch (FileNotFoundException e) {
            throw new RuntimeException(e);
        }
    }

    static class Cell{
        public int x,y;
        public Cell(int x,int y) {
            this.x = x;
            this.y = y;
        }
    }

    private boolean check_tail_increasing(int steps) {
        if (steps <= 10) {
            return true;
        }
        if (steps % 3 == 1) {
            return true;
        }
        return false;
    }

    public List<Cell> getCells(int sx,int sy,String steps) {
        steps = steps.substring(1,steps.length() - 1); // 去掉编码时加的'()'
        List<Cell> res = new ArrayList<>();

        int []dx = {-1,0,1,0}, dy = {0,1,0,-1};
        int x = sx, y = sy;
        int step = 0;
        res.add(new Cell(x,y));
        for (int i = 0; i < steps.length(); i++) {
            int d = steps.charAt(i) - '0';
            x += dx[d];
            y += dy[d];
            res.add(new Cell(x,y));
            step++;
            if (!check_tail_increasing(step)) {
                res.remove(0);
            }
        }
        return res;
    }

    public Integer nextMove(String input) {
        String[] strs = input.split("#");
        int [][] g = new int[13][14];
        for (int i = 0,k = 0; i < 13; i++) {
            for (int j = 0; j < 14; j++,k++) {
                if (strs[0].charAt(k) == '1')
                    g[i][j] = 1;
            }
        }

        int aSx = Integer.parseInt(strs[1]), aSy = Integer.parseInt(strs[2]);
        int bSx = Integer.parseInt(strs[4]), bSy = Integer.parseInt(strs[5]);
        
        // 蛇的身体标记为1
        List<Cell> cellsA = getCells(aSx,aSy,strs[3]);
        List<Cell> cellsB = getCells(bSx,bSy,strs[6]);

        
        for (Cell c: cellsA) g[c.x][c.y] = 1;
        for (Cell c: cellsB) g[c.x][c.y] = 1;
        
        int[] dx = {-1,0,1,0};
        int[] dy = {0,1,0,-1};
        for (int i = 0; i < 4; i++) {
            // 蛇尾坐标,cellsA表示自己的那条蛇
            int x = cellsA.get(cellsA.size() - 1).x + dx[i];
            int y = cellsA.get(cellsA.size() - 1).y + dy[i];
            if (x >= 0 && x < 13 && y >= 0 && y < 14 && g[x][y] == 0) {
                return i; // 可以走的位置
            }
        }
        return 0; // 向上走
    }
}