Submission #888949

#	Time	Username	Problem	Language	Result	Execution time	Memory
888949		Alihan_8	Passport (JOI23_passport)	C++17	54 / 100	2057 ms	290384 KiB

passport

#include <bits/stdc++.h>

using namespace std;

#define all(x) x.begin(), x.end()
#define ar array
#define pb push_back
#define ln '\n'
#define int long long

using i64 = long long;

template <class F, class _S>
bool chmin(F &u, const _S &v){
    bool flag = false;
    if ( u > v ){
        u = v; flag |= true;
    }
    return flag;
}

template <class F, class _S>
bool chmax(F &u, const _S &v){
    bool flag = false;
    if ( u < v ){
        u = v; flag |= true;
    }
    return flag;
}

const int inf = 1e15 + 1;

struct Sparse{
    vector <vector<int>> T;
    vector <int> A;
    int _s;
    Sparse(auto &a, int s){
        int n = a.size();
        T.resize(20);
        _s = s; A = a;
        for ( auto &j: A ) j *= s;
        for ( auto &x: T ) x.resize(n);
        for ( int i = 0; i < n; i++ ){
            T[0][i] = i;
        }
        for ( int i = 1; i < 20; i++ ){
            int k = 1 << i - 1;
            for ( int j = 0; j < n; j++ ){
                if ( A[T[i - 1][j]] < A[T[i - 1][min(n - 1, j + k)]] ){
                    T[i][j] = T[i - 1][j];
                } else T[i][j] = T[i - 1][min(n - 1, j + k)];
            }
        }
    }
    int get(int l, int r){
        int lg = __lg(r - l + 1), k = 1 << lg;
        int u = T[lg][l], v = T[lg][r - k + 1];
        return A[u] < A[v] ? u : v;
    }
};

const int N = 2e5 + 1;

int S;

struct SegTree{
    int T[N * 4];
    SegTree(){
        for ( int i = 0; i < N * 4; i++ ){
            T[i] = inf;
        }
    }
    void upd(int v, int l, int r, int pos, int val){
        if ( l == r ){
            T[v] = val;
            return;
        }
        int md = (l + r) >> 1;
        if ( pos > md ){
            upd(v * 2 + 1, md + 1, r, pos, val);
        } else{
            upd(v * 2, l, md, pos, val);
        }
        T[v] = min(T[v * 2], T[v * 2 + 1]);
    };
    void upd(int pos, int val){
        upd(1, 0, S - 1, pos, val);
    }
    int get(int v, int l, int r, int tl, int tr){
        if ( l > tr or r < tl ){
            return inf;
        }
        if ( tl <= l && tr >= r ){
            return T[v];
        }
        int md = (l + r) >> 1;
        return min(get(v * 2, l, md, tl, tr), get(v * 2 + 1, md + 1, r, tl, tr));
    }
    int get(int l, int r){
        return get(1, 0, S - 1, l, r);
    }
} seg;

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n; cin >> n;
    S = n;
    vector <int> L(n), R(n);
    for ( int i = 0; i < n; i++ ){
        cin >> L[i] >> R[i];
        --L[i], --R[i];
    }
    Sparse mn(L, 1), mx(R, -1);
    vector <int> p(n);
    iota(all(p), 0);
    sort(all(p), [&](int &x, int &y){
         return R[x] - L[x] > R[y] - L[y];
    });
    vector <unordered_map<int,int>> dp(n);
    dp[0][n - 1] = 0;
    auto dfs = [&](auto dfs, int l, int r) -> int{
        if ( dp[l].count(r) ){
            return dp[l][r];
        }
        int ret = inf, L_ = mn.get(l, r), R_ = mx.get(l, r);
        if ( R[R_] > r ){
            chmin(ret, dfs(dfs, min(L[R_], l), R[R_]) + 1);
        }
        if ( L[L_] < l ){
            chmin(ret, dfs(dfs, L[L_], max(r, R[L_])) + 1);
        }
        return dp[l][r] = min(seg.get(l, r), ret);
    };
    int q; cin >> q;
    int s; cin >> s;
    --s;
    if ( q == 1 && !s ){
        int ans = 0, lst = -1;
        bool flag = true;
        priority_queue <int> q;
        q.push(R[s]);
        for ( int i = 1; i < n; i++ ){
            if ( lst < i ){
                if ( q.empty() || q.top() < i ){
                    flag = false;
                    break;
                }
                lst = q.top();
                q.pop(); ++ans;
            } q.push(R[i]);
        }
        cout << (flag ? ans : -1) << ln;
        return 0;
    }
    vector <int> ans(n);
    for ( auto &i: p ){
        ans[i] = dfs(dfs, L[i], R[i]) + 1;
        seg.upd(i, ans[i]);
    } q--;
    cout << (ans[s] >= inf ? -1 : ans[s]) << ln;
    while ( q-- ){
        int x; cin >> x;
        --x;
        cout << (ans[x] >= inf ? -1 : ans[x]) << ln;
    }

    cout << '\n';
}

Compilation message (stderr)

passport.cpp:37:12: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
   37 |     Sparse(auto &a, int s){
      |            ^~~~
passport.cpp: In instantiation of 'Sparse::Sparse(auto:23&, long long int) [with auto:23 = std::vector<long long int>]':
passport.cpp:115:19:   required from here
passport.cpp:47:28: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   47 |             int k = 1 << i - 1;
      |                          ~~^~~

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