Submission #541689

#	Time	Username	Problem	Language	Result	Execution time	Memory
541689		cristi_a	Lightning Rod (NOI18_lightningrod)	C++17	100 / 100	1740 ms	227792 KiB

Main

#include <bits/stdc++.h>
using namespace std;

bool cover(pair<int,int> a, pair<int,int> b) {
    return abs(a.first-b.first) <= a.second - b.second;
}

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

    int n; cin >> n;
    vector<pair<int,int>> v(n);
    for(int i=0; i<n; i++) cin >> v[i].first >> v[i].second;
    stack<pair<int,int>> st;
    for(int i=0; i<n; i++) {
        while(!st.empty() and cover(v[i], st.top())) st.pop();
        if(st.empty()) st.emplace(v[i]);
        else if(!cover(st.top(), v[i])) st.emplace(v[i]);
    }
    cout << st.size();
    return 0;
}

• 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