Submission #930289

#	Time	Username	Problem	Language	Result	Execution time	Memory
930289		vjudge1	Lightning Rod (NOI18_lightningrod)	C++17	100 / 100	1361 ms	247948 KiB

Main

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

#define ll long long
#define ld long double
#define ull unsigned long long
#define pii pair<int,int>
#define pll pair<long long, long long>
#define fi first
#define se second
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define lwb lower_bound
#define upb upper_bound

#define TASKNAME "NAME"

void init()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    ///freopen(TASKNAME".INP","r",stdin); freopen(TASKNAME".OUT","w",stdout);
}

const int SZ = 1e7+5;
const ll INF = INT_MAX / 2, MOD = 1e9+7, INFLL = 2e18;
const double epsilon = 1e-3;

int n;
pii a[SZ];
vector<int> vec;

bool check(int i, int j)
{
    return abs(a[i].fi - a[j].fi) <= a[i].se - a[j].se;
}

int main()
{
    init();
    cin >> n;
    for(int i = 1; i <= n; i++)
    {
        cin >> a[i].fi >> a[i].se;
        if(!vec.empty() && check(vec.back(), i)) continue;
        while(!vec.empty() && check(i, vec.back())) vec.pop_back();
        vec.pb(i);
    }
    cout << vec.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