Submission #743160

#	Time	Username	Problem	Language	Result	Execution time	Memory
743160		vjudge1	Lightning Rod (NOI18_lightningrod)	C++17	40 / 100	2091 ms	205192 KiB

Main

#include <bits/stdc++.h>
#define x first
#define y second
using namespace std;
const int N = 1e7 + 1;
pair<int,int> arr[N];
map<pair<int,int>, bool> mp;
bool comp(const pair<int,int> &a, const pair<int,int> &b) {
    if (a.second != b.second) return a.second > b.second;
    return a.first > b.first;
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);
    int n,ans=0; cin >> n;
    for(int i=1;i<=n;i++) cin >> arr[i].x >> arr[i].y;
    if (n>2000) {
        set<int> s;
        for(int i=1;i<=n;i++) {
            s.insert(arr[i].x);
        }
        cout << s.size();
        return 0;
    }
    
    sort(arr+1, arr+1+n, comp);
    for(int i=1;i<=n;i++) {
        bool check = false;
        for(auto [a,b]:mp) {
            if (abs(arr[i].x - a.x) <= abs(arr[i].y - a.y)) check = true;
        }
        if (!check) {
            ans++;
            mp[arr[i]] = true;
        }
    }
    cout << ans;
    return 0;
}

• Subtask 1: 0 / 4
• Subtask 2: 7 / 7
• Subtask 3: 12 / 12
• Subtask 4: 21 / 21
• Subtask 5: 0 / 26
• Subtask 6: 0 / 10
• Subtask 7: 0 / 20