Submission #1257314

#	Time	Username	Problem	Language	Result	Execution time	Memory
1257314		son2008	Passport (JOI23_passport)	C++20	100 / 100	431 ms	80536 KiB

passport

#include <bits/stdc++.h>
using namespace std;
#define ii pair<int, int>
#define fi first
#define se second
// #define int long long
#define ll long long
#define ld double
#define mp make_pair
#define lg2 30
#define iii pair<int, ii>
#define iiii pair<ii, ii>
#define base 29
#define eps 1e-8
#define MASK(i) (1LL << (i))
#define BIT(S, i) (((S) >> (i)) & 1)
int dx[] = {0LL, 0LL, 1, -1, 1, 1, -1, -1};
int dy[] = {1, -1, 0LL, 0LL, 1, -1, 1, -1};
const int maxn = 2e5 + 5, inf = 1e9;
const int mod = 1e9 + 7;
int pos[maxn], n, q, dist1[maxn << 2], distn[maxn << 2], dis[maxn << 2];
vector<ii> a[maxn << 2];
void build(int id, int l, int r)
{
    if (l == r)
    {
        pos[l] = id;
        return;
    }
    int mid = (l + r) / 2;
    build(id << 1, l, mid);
    build(id << 1 | 1, mid + 1, r);
    a[id << 1].push_back({id, 0});
    a[id << 1 | 1].push_back({id, 0});
}
void update(int id, int l, int r, int u, int v, int vt)
{
    if (u > r || v < l)
        return;
    if (u <= l && v >= r)
    {
        a[id].push_back({vt, 1});
        return;
    }
    int mid = (l + r) >> 1;
    update(id << 1, l, mid, u, v, vt);
    update(id << 1 | 1, mid + 1, r, u, v, vt);
}
void dijk(int dist[], int st)
{
    priority_queue<ii, vector<ii>, greater<ii>> pq;
    dist[pos[st]] = 0;
    pq.push({0, pos[st]});
    while (!pq.empty())
    {
        ii t = pq.top();
        pq.pop();
        if (dist[t.se] != t.fi)
            continue;
        for (auto v : a[t.se])
        {
            if (dist[v.fi] > dist[t.se] + v.se)
            {
                dist[v.fi] = dist[t.se] + v.se;
                pq.push({dist[v.fi], v.fi});
            }
        }
    }
}
signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
#define task "task"
    if (fopen(task ".inp", "r"))
    {
        freopen(task ".inp", "r", stdin);
        freopen(task ".out", "w", stdout);
    }
    cin >> n;
    build(1, 1, n);
    for (int i = 1; i <= n; i++)
    {
        int l, r;
        cin >> l >> r;
        update(1, 1, n, l, r, pos[i]);
    }
    for (int i = 1; i <= 4 * n; i++)
    {
        dist1[i] = distn[i] = dis[i] = inf;
    }
    dijk(dist1, 1);
    dijk(distn, n);
    priority_queue<ii, vector<ii>, greater<ii>> pq;
    for (int i = 1; i <= n; i++)
    {
        // cout << distn[pos[i]] << " ";
        if (dist1[pos[i]] == inf || distn[pos[i]] == inf)
            continue;
        dis[pos[i]] = dist1[pos[i]] + distn[pos[i]] - (i != 1 && i != n);
        pq.push({dis[pos[i]], pos[i]});
    }
    while (!pq.empty())
    {
        ii t = pq.top();
        pq.pop();
        if (dis[t.se] != t.fi)
            continue;
        for (auto v : a[t.se])
        {
            if (dis[v.fi] > dis[t.se] + v.se)
            {
                dis[v.fi] = dis[t.se] + v.se;
                pq.push({dis[v.fi], v.fi});
            }
        }
    }
    int q;
    cin >> q;
    while (q--)
    {
        int x;
        cin >> x;
        if (dis[pos[x]] == inf)
        {
            cout << -1 << '\n';
        }
        else
            cout << dis[pos[x]] << '\n';
    }
    cerr << endl
         << "TIME : " << clock() * 0.001 << "s" << endl;
}

Compilation message (stderr)

passport.cpp: In function 'int main()':
passport.cpp:78:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   78 |         freopen(task ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
passport.cpp:79:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   79 |         freopen(task ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

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