Submission #590025

#	Time	Username	Problem	Language	Result	Execution time	Memory
590025		Valaki2	Road Construction (JOI21_road_construction)	C++14	100 / 100	1609 ms	14832 KiB

road_construction

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

#define int long long
#define pb push_back
#define pii pair<int, int>
#define mp make_pair
#define fi first
#define se second

const int inf = 4e9 + 42;

int n, k;
vector<pii > points;

inline int new_x(pii a) {
    return a.fi - a.se;
}

inline int new_y(pii a) {
    return a.fi + a.se;
}

inline int dist(pii a, pii b) {
    return abs(a.fi - b.fi) + abs(a.se - b.se);
}

bool cmp_1(pii a, pii b) {
    if(new_x(a) == new_x(b)) {
        return (a.fi < b.fi);
    }
    return new_x(a) < new_x(b);
}

struct cmp_2 {
    bool operator()(const pii &a, const pii &b) {
        if(new_y(a) == new_y(b)) {
            return (a.se < b.se);
        }
        return new_y(a) < new_y(b);
    }
};

vector<int> real_ans;

bool check(int l) {
    set<pii, cmp_2> s;
    vector<int> ans;
    int idx_2 = 0;
    for(int idx_1 = 0; idx_1 < n; idx_1++) {
        while(idx_2 < idx_1 && (new_x(points[idx_1]) - new_x(points[idx_2])) > l) {
            s.erase(s.find(points[idx_2]));
            idx_2++;
        }
        pii cur = points[idx_1];
        auto it = s.lower_bound(mp(cur.fi, cur.se - l));
        while(it != s.end()) {
            pii nei = *it;
            int d = dist(cur, nei);
            if(d <= l) {
                ans.pb(d);
                if((int) ans.size() >= k + 1) {
                    return false;
                }
            } else {
                break;
            }
            it++;
        }
        s.insert(cur);
    }
    real_ans = ans;
    return true;
}

void solve() {
    cin >> n >> k;
    points.assign(n, mp(0, 0));
    for(int i = 0; i < n; i++) {
        cin >> points[i].fi >> points[i].se;
    }
    sort(points.begin(), points.end(), cmp_1);
#ifdef __DEBUG__
    for(pii p : points) {
        cout << p.fi << " " << p.se << "\n";
    }
#endif
    int l = 1, r = inf;
    while(l < r - 1) {
        int mid = (l + r) / 2;
        if(check(mid)) {
            l = mid;
        } else {
            r = mid;
        }
    }
#ifdef __DEBUG__
    cout << l << "\n";
    cout << "-----\n";
#endif
    check(l);
    sort(real_ans.begin(), real_ans.end());
    real_ans.resize(k, r);
    for(int cur : real_ans) {
        cout << cur << "\n";
    }
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    solve();
    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 7 / 7
• Subtask 4: 20 / 20
• Subtask 5: 27 / 27
• Subtask 6: 35 / 35