Submission #1110520

#	Time	Username	Problem	Language	Result	Execution time	Memory
1110520		onbert	Road Construction (JOI21_road_construction)	C++17	5 / 100	1984 ms	32708 KiB

road_construction

#include <bits/stdc++.h>
using namespace std;
#define int long long
const int maxn = 250005, maxN = 1e6 + 5, INF = 1e10;
int n, k;
pair<int,int> a[maxn];
int sz;
vector<int> vals = {-INF};
int ldc(int x) {return lower_bound(vals.begin(), vals.end(), x) - vals.begin();}
int rdc(int x) {return upper_bound(vals.begin(), vals.end(), x) - vals.begin() - 1;}

struct node {
    int lpt, rpt, val;
};

struct thing {
    int id, dist, cnt;
    bool operator < (const thing &b) const {
        return dist > b.dist;
    }
};

vector<node> seg[maxn];
void build(int id, int l, int r) {
    seg[id] = {{0, 0, 0}};
    if (l==r) return;
    int mid = (l+r)/2;
    build(id*2, l, mid); build(id*2+1, mid+1, r);
}
void update(int id, int l, int r, int target) {
    if (r<target || target<l) return;
    if (l==r) {
        int val = seg[id].back().val + 1;
        seg[id].push_back({0, 0, val});
        return;
    }
    int mid = (l+r)/2;
    update(id*2, l, mid, target);
    update(id*2+1, mid+1, r, target);
    int val = seg[id*2].back().val + seg[id*2+1].back().val;
    seg[id].push_back({(int)seg[id*2].size() - 1, (int)seg[id*2+1].size() - 1, val});
}
int qry(int id, int pt, int l, int r, int findl, int findr) {
    if (r<findl || findr<l) return 0;
    if (findl<=l && r<=findr) return seg[id][pt].val;
    int mid = (l+r)/2;
    int lhs = qry(id*2, seg[id][pt].lpt, l, mid, findl, findr);
    int rhs = qry(id*2+1, seg[id][pt].rpt, mid+1, r, findl, findr);
    return lhs + rhs;
}


int cunt(int id, int dist) {
    int L = ldc(a[id].second - dist), R = rdc(a[id].second + dist);
    int val = qry(1, id, 1, sz, L, R);
    int x = lower_bound(a+1, a+n+1, make_pair(a[id].first - dist, -INF)) - a - 1;
    // cout << val << " " << x << endl;
    val -= qry(1, x, 1, sz, L, R);
    return val;
}

signed main() {
    ios::sync_with_stdio(0); cin.tie(0);
    cin >> n >> k;
    for (int i=1;i<=n;i++) {
        int x, y;
        cin >> x >> y;
        a[i] = {x+y, x-y};
        vals.push_back(x-y);
    }
    sort(a+1, a+n+1);
    sort(vals.begin(), vals.end());
    vals.erase(unique(vals.begin(), vals.end()), vals.end());
    sz = vals.size() - 1;
    build(1, 1, sz);
    for (int i=1;i<=n;i++) update(1, 1, sz, ldc(a[i].second));
    pair<int,int> b[n+1];
    priority_queue<thing> pq;
    for (int i=2;i<=n;i++) {
        b[i] = {0, 1};
        int l = b[i].first+1, r = INF;
        while (l < r) {
            int mid = (l+r)/2;
            if (cunt(i, mid) == b[i].second) l = mid+1;
            else r = mid;
        }
        pq.push({i, l, cunt(i, l)});
        // cout << i << " " << l << " " << cunt(i, l) << endl;
    }
    int total = 0;
    while (true) {
        int dist = pq.top().dist, cnt = pq.top().cnt, id = pq.top().id;
        pq.pop();
        // cout << id << " " << b[id].second << " " << cnt << endl;
        if (id==2 && b[id].second==2) return 0;
        for (;b[id].second<cnt;b[id].second++) {
            cout << dist << '\n';
            total++;
            if (total == k) return 0;
        }
        if (b[id].second == id) continue;
        b[id].first = dist;
        int l = dist+1, r = INF;
        while (l < r) {
            int mid = (l+r)/2;
            if (cunt(id, mid) == b[id].second) l = mid+1;
            else r = mid;
        }
        pq.push({id, l, cunt(id, l)});
    }
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 6
• Subtask 3: 0 / 7
• Subtask 4: 0 / 20
• Subtask 5: 0 / 27
• Subtask 6: 0 / 35