제출 #1264142

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1264142		sohamsen15	Lightning Rod (NOI18_lightningrod)	C++20	66 / 100	1103 ms	156348 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;

void counting_sort(vector<pair<int,int>> &a, int exp, int base) {
    int n = a.size();
    vector<pair<int,int>> output(n);
    vector<int> count(base, 0);

    for (int i = 0; i < n; i++) {
        int digit = (a[i].first / exp) % base;
        count[digit]++;
    }

    for (int i = 1; i < base; i++) {
        count[i] += count[i - 1];
    }

    for (int i = n - 1; i >= 0; i--) {
        int digit = (a[i].first / exp) % base;
        output[count[digit] - 1] = a[i];
        count[digit]--;
    }

    a = move(output);
}

void radix_sort_pairs(vector<pair<int,int>> &a) {
    if (a.empty()) return;
    int mx = 0;
    for (auto &p : a) mx = max(mx, p.first);

    int base = 10;
    for (int exp = 1; mx / exp > 0; exp *= base) {
        counting_sort(a, exp, base);
    }
}

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; }
    vector<pair<int, int>> p(n); for (int i = 0; i < n; i++) cin >> p[i].F >> p[i].S;
    radix_sort_pairs(p);
    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