[C++知识库]很好的练手stl的题 AtCoder Beginner Contest 243-C Collision 2

C - Collision 2 (atcoder.jp)

#include <iostream>
#include <algorithm>
#include <map>
#include <vector>

using namespace std;
#define x first
#define y second
const int M = 1e6;
typedef pair<int, int>pill;
pill p[M];
map<int, vector<pill>>mp;

int main()
{


	int n;
	cin >> n;
	for (int i = 0; i < n; i++)
	{
		cin >> p[i].x >> p[i].y;
	}
	string str;
	cin >> str;
	for (int i = 0; i < n; i++)
	{
		mp[p[i].y].push_back({ p[i].x,str[i] == 'R' ? 0 : 1 });
	}

	for (auto i : mp)
	{
		sort(i.y.begin(), i.y.end(), [](pill a, pill b)
			{
				return a.x < b.x;
			}

		);
		int l = i.y.size();
		for (int j = 0; j <l ; j++)
		{
			if (i.y[j].y == 0)
			{
				for (int k = j + 1; k < l; k++)
				{
					if (i.y[k].y == 1)
					{
						cout << "Yes" << endl;

						return 0;
					}
				}
			}
			
		}


	}
	cout << "No" << endl;


	return 0;
}

不过用STL可能有点绕 所以也可以用结构体排序

//#pragma GCC optimize(2)
#include <cstdio>
#include <cstring>
#include <cmath>
#include <map>
#include <vector>
#include <ctime>
#include <string>
#include <iostream>
#include <algorithm>
using namespace std;
using ll = long long;
const int N = 2e5 + 7;
const long long INF = 0x3f3f3f3f3f3f3f3f;
typedef pair<int, int> PII;
#define ff first
#define ss second

PII p[N];
char str[N];
map<int, vector<PII>> mp;
int n;
struct f
{
    int x;
    int y;
    char s;
}q[N];
void init()
{
    cin >> n;
    for (int i = 0; i < n; i++)
    {
        cin >> q[i].x >> q[i].y;
    }
    string st;
    cin >> st;
    for (int i = 0; i < n; i++)
    {
        q[i].s = st[i];
    }
}

void work()
{
    sort(q, q + n, [](f a, f b)
        {
            if (a.y == b.y)
            {
                return a.x < b.x;
            }
            return a.y < b.y;
        }
    );

    for (int i = 0; i < n-1; i++)
    {
        if (q[i].y == q[i + 1].y && q[i].s == 'R' && q[i + 1].s == 'L')
        {
            cout << "Yes" << endl;
            return;
        }

    }
    cout << "No" << endl;



}

int main() {
    int T = 1;
    //    scanf("%d",&T);

    while (T--) {

        init();
        work();
    }
    return 0;
}