Submission #496809

#	Time	Username	Problem	Language	Result	Execution time	Memory
496809		SirCovidThe19th	Lightning Rod (NOI18_lightningrod)	C++17	66 / 100	2024 ms	262148 KiB

Main

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

#define FOR(i, x, y) for (int i = x; i < y; i++)
#define pii pair<int, int>
#define f first
#define s second

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); 
    int n; cin >> n; 
    bool covered[n] = {}; pii A[n]; set<pii> S;

    FOR(i, 0, n){
        cin >> A[i].f >> A[i].s;
        while (!S.empty() and prev(S.end())->f >= A[i].f - A[i].s){
            covered[prev(S.end())->s] = 1;
            S.erase(prev(S.end()));
        }
        S.insert({A[i].f - A[i].s, i});
    }
    S.clear();
    for (int i = n - 1; ~i; i--) if (!covered[i]){
        while (!S.empty() and S.begin()->f <= A[i].f + A[i].s){
            covered[S.begin()->s] = 1;
            S.erase(S.begin());
        }
        S.insert({A[i].f + A[i].s, i});
    }
    cout<<n - accumulate(covered, covered + n, 0)<<endl;
}

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