Submission #1264143

#	Time	Username	Problem	Language	Result	Execution time	Memory
1264143		sohamsen15	Lightning Rod (NOI18_lightningrod)	C++20	66 / 100	1104 ms	170524 KiB

Main

#pragma GCC optimize("Ofast,unroll-loops")
#include <bits/stdc++.h>
#define F first 
#define S second
using namespace std;
using ll = long long;

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

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    cout << fixed << setprecision(0);

    int n, ans = 0; cin >> n; if (n == 1) { cout << 1; return 0; }
    set<pair<int, int>> q; for (int i = 0; i < n; i++) { int x, y; cin >> x >> y; q.insert({x, y}); }
    vector<pair<int, int>> p; for (auto x: q) p.push_back(x);
    vector<int> a(n), b(n), maxal(n), minbr(n);
    for (int i = 0; i < n; i++) a[i] = p[i].F + p[i].S, b[i] = p[i].F - p[i].S;
    maxal[0] = a[0]; minbr[n - 1] = b[n - 1];
    for (int i = 1; i < n; i++) maxal[i] = max(maxal[i - 1], a[i]);
    for (int i = n - 2; i >= 0; i--) minbr[i] = min(minbr[i + 1], b[i]);
    ans += (b[0] < minbr[1]) + ((a[n - 1] > maxal[n - 2]));
    for (int i = 1; i < n - 1; i++) ans += (b[i] < minbr[i + 1] && a[i] > maxal[i - 1]);
    cout << ans;
}

• 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