Submission by @__dAi00

#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
#include <tuple>
#include <string>
#include <utility>
using namespace std;
const int dx[] = { 1,0,-1,0,0 };
const int dy[] = { 0,1,0,-1,0 };
const string dir = "ESWNX";

int H, W, T, N;
string maps[22];
vector<tuple<int, int, int>> iwashi;
int iwashiMap[22][22];
int nextIwashiMap[22][22];
int distanceMap[22][22];

int main() {
	cin >> H >> W >> T >> N;
	int px, py;	cin >> px >> py;
	px--;	py--;
	for (int i = 0; i < H; i++)	cin >> maps[i];
	for (int i = 0; i < N; i++) {
		int x, y, t;	cin >> x >> y >> t;
		y--;	x--;
		iwashi.push_back(make_tuple(t, x, y));
	}
	sort(iwashi.begin(), iwashi.end());
	while (get<0>(iwashi[0]) == 0) {
		int x, y, t;
		tie(t, x, y) = iwashi[0];
		iwashiMap[y][x]++;
		iwashi.erase(iwashi.begin());
	}
	string ret = "";
	int score = 0;
	int paralyzed = 0;
	for (int t = 1; t < T; t++) {
		// player move(ここを実装してください)

		// iwashi move
		for (int i = 0; i < H; i++)	for (int j = 0; j < W; j++)	nextIwashiMap[i][j] = 0;
		for (int i = 0; i < H; i++)	for (int j; j < W; j++) {
			if (maps[i][j] == '#')	continue;
			if (nextIwashiMap[i][j] > 0) {
				nextIwashiMap[i][j] += iwashiMap[i][j];
				continue;
			}
			queue<pair<int, int>> q;
			for (int y = 0; y < H; y++)	for (int x = 0; x < W; x++) {
				if (maps[y][x] != '#' && iwashiMap[y][x] > 0 && !(y == i && x == j)) {
					distanceMap[y][x] = 0;
					q.push(make_pair(y, x));
				}
				else	distanceMap[y][x] = W * H;
			}
			if (paralyzed == 0) {
				distanceMap[py][px] = 0;
				q.push(make_pair(py, px));
			}
			while (!q.empty()) {
				int x = q.front().second, y = q.front().first;
				q.pop();
				for (int k = 0; k < 4; k++) {
					int nx = x + dx[k];
					int ny = y + dy[k];
					if (maps[ny][nx] == '#')	continue;
					if (distanceMap[y][x] + 1 < distanceMap[ny][nx]) {
						distanceMap[ny][nx] = distanceMap[y][x] + 1;
						q.push(make_pair(ny, nx));
					}
				}
			}
			for (int k = 0; k < 5; k++) {
				int ny = i + dy[k];
				int nx = j + dx[k];
				if (maps[ny][nx] == '#')	continue;
				if (distanceMap[i][j] > distanceMap[ny][nx] || k == 4) {
					nextIwashiMap[ny][nx] += iwashiMap[i][j];
					break;
				}
			}
		}
		for (int i = 0; i < H; i++)	for (int j = 0; j < W; j++)	iwashiMap[i][j] = nextIwashiMap[i][j];

		// iwashi つちからはえてくるんだ
		while ((!iwashi.empty()) && get<0>(iwashi[0]) == t) {
			int x, y, hogeT;
			tie(hogeT, x, y) = iwashi[0];
			iwashiMap[y][x]++;
			iwashi.erase(iwashi.begin());
		}
		// scoreing
		if (paralyzed > 0) {
			paralyzed--;
		}
		else if (0 < iwashiMap[py][px] && iwashiMap[py][px] <= 5) {
			score += iwashiMap[py][px];
			iwashiMap[py][px] = 0;
		}
		else if (iwashiMap[py][px] > 5) {
			paralyzed += 5;
			iwashiMap[py][px] = 0;
		}
	}
	cout << ret << endl;
	return 0;
}

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