[ABC303C] Dash

直接模拟即可。

#include <bits/stdc++.h>
using namespace std;

const int N = 2e5 + 5;

int dx[] = { 0, 0, -1, 1 };
int dy[] = { -1, 1, 0, 0 };

int n, m, h, k;
string s;
set<pair<int, int> > st;

int main()
{
	scanf("%d%d%d%d", &n, &m, &h, &k);
	cin >> s;
	int nowx = 0, nowy = 0;
	for (int i = 1; i <= m; i++)
	{
		int x, y;
		scanf("%d%d", &x, &y);
		st.insert(make_pair(x, y));
	}
	for (int i = 0; i < s.size(); i++)
	{
		char c = s[i];
		if (c == 'R') nowx++;
		else if (c == 'L') nowx--;
		else if (c == 'D') nowy--;
		else nowy++;
		h--;
		if (h < 0)
		{
			printf("No\n");
			return 0;
		}
		if (st.count(make_pair(nowx, nowy)) && h < k)
		{
			st.erase(make_pair(nowx, nowy));
			h = k;
		}
	}
	printf("Yes\n");
	return 0;
}