코드

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

public class Main {

    static int N, M, A, B;
    static Map<String, Direction> directions = new HashMap<>();
    static String[] robotsDirection;
    static int[][] robots, map;

    public static void main(String[] args) throws IOException {
        //initialize
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine());

        A = Integer.parseInt(st.nextToken());
        B = Integer.parseInt(st.nextToken());

        st = new StringTokenizer(br.readLine());
        N = Integer.parseInt(st.nextToken());
        M = Integer.parseInt(st.nextToken());

        robots = new int[N + 1][2];
        map = new int[B + 1][A + 1];
        robotsDirection = new String[N + 1];

        initialize();
        for (int i = 1; i <= N; i++) {
            st = new StringTokenizer(br.readLine());
            int x = Integer.parseInt(st.nextToken());
            int y = Integer.parseInt(st.nextToken());
            robots[i][0] = y;
            robots[i][1] = x;
            robotsDirection[i] = st.nextToken();
            map[y][x] = i;
        }

        for (int i = 0; i < M; i++) {
            st = new StringTokenizer(br.readLine());
            int robotNum = Integer.parseInt(st.nextToken());
            String command = st.nextToken();
            int commandCount = Integer.parseInt(st.nextToken());

            for (int count = 0; count < commandCount; count++) {
                if (!executeCommand(robotNum, command)) return;
            }
        }

        System.out.println("OK");
    }

    private static void initialize() {
        directions.put("E", new Direction("N", "S", new int[]{0, 1}));
        directions.put("S", new Direction("E", "W", new int[]{-1, 0}));
        directions.put("N", new Direction("W", "E", new int[]{1, 0}));
        directions.put("W", new Direction("S", "N", new int[]{0, -1}));
    }

    private static boolean executeCommand(int robotNum, String command) {
        if (command.equals("F")) return goForward(robotNum);
        else if (command.equals("L")) return turnLeft(robotNum);
        else return turnRight(robotNum);
    }

    private static boolean goForward(int robotNum) {
        String currentDirection = robotsDirection[robotNum];

        Direction info = directions.get(currentDirection);

        int[] diff = info.F;
        int ny = diff[0] + robots[robotNum][0];
        int nx = diff[1] + robots[robotNum][1];

        if (ny > B || ny <= 0 || nx > A || nx <= 0) {
            System.out.println("Robot " + robotNum + " crashes into the wall");
            return false;
        }

        if (map[ny][nx] != 0) {
            System.out.println("Robot " + robotNum + " crashes into robot " + map[ny][nx]);
            return false;
        }

        robots[robotNum][0] = ny;
        robots[robotNum][1] = nx;
        map[ny][nx] = robotNum;
        map[ny - diff[0]][nx - diff[1]] = 0;

        return true;
    }

    private static boolean turnLeft(int robotNum) {
        String currentDirection = robotsDirection[robotNum];

        Direction info = directions.get(currentDirection);

        robotsDirection[robotNum] = info.L;

        return true;
    }

    private static boolean turnRight(int robotNum) {
        String currentDirection = robotsDirection[robotNum];

        Direction info = directions.get(currentDirection);

        robotsDirection[robotNum] = info.R;

        return true;
    }

    static class Direction {
        String L, R;
        int[] F;

        public Direction(String l, String r, int[] f) {
            L = l;
            R = r;
            F = f;
        }
    }
}

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