Submission #743941

#	Time	Username	Problem	Language	Result	Execution time	Memory
743941		vjudge1	Lightning Rod (NOI18_lightningrod)	C++17	100 / 100	1927 ms	171544 KiB

Main

#include<bits/stdc++.h>

using namespace std;

using ll = long long ;
using pii = pair<ll , ll> ;
using i3 = tuple<ll , ll , ll> ;

const int N = 2e5+5  ;
const int MOD = 1e9+7 ;

int n ;

map<pii , bool> vis ;

struct Points {
    int x , y ;
};

vector<Points> point ;

stack<Points> st ;

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);

    cin >> n ;
    for(int i=0;i<n;i++){
        int x , y ; cin >> x >> y ;
        point.push_back({x , y}) ;
    }

    for(int i=0;i<n;i++){
        while(!st.empty() && point[i].y - st.top().y >= point[i].x - st.top().x){
            st.pop();
        }
        if(st.empty() || !(st.top().y - point[i].y >= point[i].x - st.top().x))
            st.push(point[i]);
    }
    cout << st.size() ;
}

• Subtask 1: 4 / 4
• Subtask 2: 7 / 7
• Subtask 3: 12 / 12
• Subtask 4: 21 / 21
• Subtask 5: 26 / 26
• Subtask 6: 10 / 10
• Subtask 7: 20 / 20