Submission #873106

#	Time	Username	Problem	Language	Result	Execution time	Memory
873106		boris_mihov	Passport (JOI23_passport)	C++17	0 / 100	356 ms	569980 KiB

passport

#include <algorithm>
#include <iostream>
#include <numeric>
#include <cassert>
#include <vector>
#include <queue>

typedef long long llong;
const int MAXN = 200000 + 10;
const int INF = 1e9;

int n;
std::vector <std::pair <int,int>> g[MAXN];
struct SegmentTree
{
    int cnt;
    int tree[4*MAXN];

    void build(int l, int r, int node)
    {
        if (l == r)
        {
            tree[node] = l;
            return;
        }

        tree[node] = ++cnt;
        int mid = (l + r) / 2;
        build(l, mid, 2*node);
        build(mid + 1, r, 2*node + 1);
        g[tree[2 * node]].push_back({tree[node], 0});
        g[tree[2 * node + 1]].push_back({tree[node], 0});
    }

    void addEdges(int l, int r, int node, int queryL, int queryR, int queryNode)
    {
        if (queryL <= l && r <= queryR)
        {
            g[tree[node]].push_back({queryNode, 1});
            return;
        }

        int mid = (l + r) / 2;
        if (queryL <= mid) addEdges(l, mid, 2*node, queryL, queryR, queryNode);
        if (mid + 1 <= queryR) addEdges(mid + 1, r, 2*node + 1, queryL, queryR, queryNode);
    }

    void build()
    {
        cnt = n;
        build(1, n, 1);
    }

    void addEdges(int to, int l, int r)
    {
        addEdges(1, n, 1, l, r, to);
    }
};

int queries;
int l[MAXN];
int r[MAXN];
int dist[2 * MAXN];
int distA[2 * MAXN];
int distB[2 * MAXN];
std::queue <int> q[2 * MAXN];
std::deque <int> dq;
SegmentTree tree;
bool vis[MAXN];

void solve()
{
    tree.build();
    for (int i = 1 ; i <= n ; ++i)
    {
        tree.addEdges(i, l[i], r[i]);
    }   

    std::fill(distA + 1, distA + 1 + tree.cnt, INF);
    std::fill(distB + 1, distB + 1 + tree.cnt, INF);
    dq.push_back(1);
    distA[1] = 0;

    while (!dq.empty())
    {
        int top = dq.front();
        dq.pop_front();

        for (const auto &[u, d] : g[top])
        {
            if (distA[u] > distA[top] + d)
            {
                distA[u] = distA[top] + d;
                if (d == 0) dq.push_front(u);
                else dq.push_back(u);
            }
        }   
    }

    dq.push_back(n);
    distB[n] = 0;

    while (!dq.empty())
    {
        int top = dq.front();
        dq.pop_front();

        for (const auto &[u, d] : g[top])
        {
            if (distB[u] > distB[top] + d)
            {
                distB[u] = distB[top] + d;
                if (d == 0) dq.push_front(u);
                else dq.push_back(u);
            }
        }   
    }

    for (int i = 1 ; i <= n ; ++i)
    {
        dist[i] = distA[i] + distB[i] - (distA[i] > 0 && distB[i] > 0);
        if (dist[i] <= 2 * n) q[dist[i]].push(i);
    }

    for (int d = 0 ; d <= n ; ++d)
    {
        while (!q[d].empty())
        {
            int top = q[d].front();
            q[d].pop();

            if (vis[top])
            {
                continue;
            }

            vis[top] = true;
            for (const auto &[u, d] : g[top])
            {
                if (dist[u] > dist[top] + d)
                {
                    dist[u] = dist[top] + d;
                    q[dist[u]].push(u);
                }
            }
        }
    }

    for (int i = 1 ; i <= queries ; ++i)
    {
        int node;
        std::cin >> node;
        if (dist[node] <= n) std::cout << dist[node] << '\n';
        else std::cout << -1 << '\n';
    }
}

void input()
{
    std::cin >> n;
    for (int i = 1 ; i <= n ; ++i)
    {
        std::cin >> l[i] >> r[i];
    }

    std::cin >> queries;
}

void fastIOI()
{
    std::ios_base :: sync_with_stdio(0);
    std::cout.tie(nullptr);
    std::cin.tie(nullptr);
}

int main()
{
    fastIOI();
    input();
    solve();

    return 0;
}

• Subtask 1: 0 / 6
• Subtask 2: 0 / 16
• Subtask 3: 0 / 24
• Subtask 4: 0 / 8
• Subtask 5: 0 / 46