Submission #560037

#	Time	Username	Problem	Language	Result	Execution time	Memory
560037		Yazan_Alattar	Autobahn (COI21_autobahn)	C++14	50 / 100	817 ms	102864 KiB

autobahn

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define F first
#define S second
#define pb push_back
#define endl "\n"
#define all(x) x.begin(), x.end()
const int M = 2000007;
const ll inf = 2e9;
const ll mod = 1e9 + 7;
const double pi = acos(-1);
const double eps = 1e-6;
const int dx[] = {0, -1, 0, 1}, dy[] = {1, 0, -1, 0};
const int block = 320;

vector <ll> v;
ll n, k, x, l[M], t[M], r[M], cnt[M], tot[M], pref[M], ans;

void add(ll pos){
    if(pos < 0 || pos > 1e9) return;
    v.pb(pos);
    v.pb(pos + x - 1);
    v.pb(pos - x + 1);
    return;
}

ll get(ll val){
    return lower_bound(all(v), val) - v.begin() + 1;
}

int main(){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n >> k >> x;
    for(int i = 1; i <= n; ++i){
        cin >> l[i] >> t[i] >> r[i];

        for(int j = -2; j <= 2; ++j){
            add(l[i] + j);
            add(l[i] + t[i] + j);
            add(r[i] + j);
        }
    }

    sort(all(v));
    v.erase(unique(all(v)), v.end());

    for(int i = 1; i <= n; ++i){
        ++cnt[get(l[i])];
        --cnt[get(r[i] + 1)];

        ++tot[get(l[i] + t[i])];
        --tot[get(r[i] + 1)];
    }
    for(int i = 1; i <= v.size(); ++i) cnt[i] += cnt[i - 1], tot[i] += tot[i - 1];

    for(int i = 1; i <= v.size(); ++i){
        pref[i] = pref[i - 1];
        if(cnt[i - 1] >= k) pref[i] += (v[i - 1] - v[i - 2]) * tot[i - 1]; // [l, r[
    }

//    for(auto i : v) cout << i << " "; cout << endl;
//    for(int i = 1; i <= v.size(); ++i) cout << cnt[i] << " "; cout << endl;
//    for(int i = 1; i <= v.size(); ++i) cout << tot[i] << " "; cout << endl;
//    for(int i = 1; i <= v.size(); ++i) cout << pref[i] - pref[i - 1] << " "; cout << endl;

    for(int i = 0; i < v.size(); ++i){
        if(v[i] + x - 1 > 1e9) continue;

        int posi = i + 1;
        int posj = get(v[i] + x - 1);

        ans = max(ans, pref[posj] - pref[posi] + (cnt[posj] >= k) * tot[posj]);
    }
    cout << ans << endl;
    return 0;
}

Compilation message (stderr)

autobahn.cpp: In function 'int main()':
autobahn.cpp:56:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   56 |     for(int i = 1; i <= v.size(); ++i) cnt[i] += cnt[i - 1], tot[i] += tot[i - 1];
      |                    ~~^~~~~~~~~~~
autobahn.cpp:58:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |     for(int i = 1; i <= v.size(); ++i){
      |                    ~~^~~~~~~~~~~
autobahn.cpp:68:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |     for(int i = 0; i < v.size(); ++i){
      |                    ~~^~~~~~~~~~

• Subtask 1: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 0 / 50