题解 | 分数线划定

#include <bits/stdc++.h>
using namespace std;
 vector<pair<int, int>> a;
int n,m;
int main() {
    cin>>n>>m;
    int cnt=m*1.5,num=0;
    while(n--)
    {
        int x,y;
        cin>>x>>y;
        a.emplace_back(x, y);
    }
    sort(a.begin(), a.end(), [&](auto x,auto y)
    {
        if(x.second!=y.second)return x.second>y.second;
        return x.first<y.first;
    });
    int ans=a[cnt-1].second;
    for(auto z:a)
    {
        if(z.second>=ans)
        {
            num++;
        }
        else{
            break;
        }
    }
    cout<<ans<<" "<<num<<endl;
    for(auto z:a)
    {
        if(z.second>=ans)
        {
            cout<<z.first<<" "<<z.second<<endl;
        }
        else{
            break;
        }
    }
    return 0;
}