Submission #799880

#	Time	Username	Problem	Language	Result	Execution time	Memory
799880		phoenix	Advertisement 2 (JOI23_ho_t2)	C++17	100 / 100	177 ms	78820 KiB

Main

#include<bits/stdc++.h>

using namespace std;
using ll = long long;

const int N = 5e5 + 10;
vector<int> g[N];
vector<int> order;
vector<bool> us;

void topsort(int s) {
    us[s] = 1;
    for(int to : g[s]) {
        if(us[to]) continue;
        topsort(to);
    }
    order.push_back(s);
}
void dfs(int s) {
    us[s] = 1;
    for(int to : g[s]) {
        if(us[to]) continue;
        dfs(to);
    }
}

int n;
pair<ll, ll> pnts[N];
ll A[N], B[N];

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    cin >> n;
    for(int i = 1; i <= n; i++) 
        cin >> pnts[i].first >> pnts[i].second;
    sort(pnts + 1, pnts + n + 1);
    for(int i = 1; i <= n; i++) 
        A[i] = pnts[i].second - pnts[i].first,
        B[i] = pnts[i].second + pnts[i].first;
    
    vector<int> v;
    for(int i = 1; i <= n; i++) {
        while(!v.empty() && A[v.back()] <= A[i]) {
            g[i].push_back(v.back());
            v.pop_back();
        }
        v.push_back(i);
    }
    v.clear();
    for(int i = n; i >= 1; i--) {
        while(!v.empty() && B[v.back()] <= B[i]) {
            g[i].push_back(v.back());
            v.pop_back();
        }
        v.push_back(i);
    }
    us.assign(n + 1, false);
    for(int i = 1; i <= n; i++) {
        if(!us[i]) topsort(i);
    }

    reverse(order.begin(), order.end());
    us.assign(n + 1, false);
    int cmp = 0;
    for(int c : order) {
        if(!us[c]) dfs(c), cmp++;
    }
    cout << cmp;
}

• Subtask 1: 10 / 10
• Subtask 2: 23 / 23
• Subtask 3: 36 / 36
• Subtask 4: 31 / 31