Submission #890677

#	Time	Username	Problem	Language	Result	Execution time	Memory
890677		EJIC_B_KEDAX	Railway Trip 2 (JOI22_ho_t4)	C++17	16 / 100	2065 ms	61348 KiB

Main

#ifdef LOCAL
    //#define _GLIBCXX_DEBUG
#endif
#include <bits/stdc++.h>
#include <random>

#ifndef LOCAL
    //#pragma GCC optimize("O3")
    //#pragma GCC optimize("Ofast")
    //#pragma GCC optimize("unroll-loops")
    #pragma GCC target("avx,avx2,bmi,bmi2,popcnt,lzcnt")
#endif
using namespace std;
using ll = long long;
using ld = long double;
#define x first
#define y second
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()

template<typename T>
struct segment_tree_default {
    std::vector<T> a{};
    void (*mrg)(T&, const T&, const T&);
    size_t size{};
    T e;
    segment_tree_default(int n, void (*merge)(T&, const T&, const T&), T neutral) {
        mrg = merge;
        e = neutral;
        size = 1;
        while (size < n) {
            size <<= 1;
        }
        a.resize(2 * size - 1, e);
    }
    segment_tree_default() = default;
    void update_element(int ind, const T& value) {
        ind += size - 1;
        a[ind] = value;
        while (ind) {
            ind = (ind - 1) / 2;
            mrg(a[ind], a[2 * ind + 1], a[2 * ind + 2]);
        }
    }
    void update_all(std::vector<T>& values) {
        while (size < values.size()) {
            size <<= 1;
        }
        a.resize(2 * size - 1);
        for (int i = size - 1; i < 2 * size - 1; i++) {
            if (i - size + 1 < values.size()) {
                a[i] = values[i - size + 1];
            } else {
                a[i] = e;
            }
        }
        for (int i = size - 2; i >= 0; i--) {
            mrg(a[i], a[2 * i + 1], a[2 * i + 2]);
        }
    }
    T get(int l, int r, int l1 = 0, int r1 = -1, int i = 0) {
        if (r1 == -1) {
            r1 += size;
        }
        if (l1 >= l && r1 <= r) {
            return a[i];
        }
        if (r1 < l || l1 > r) {
            return e;
        }
        T res;
        mrg(res, get(l, r, l1, (l1 + r1) / 2, 2 * i + 1), get(l, r, (l1 + r1) / 2 + 1, r1, 2 * i + 2));
        return res;
    }
};

void mn(int& to, const int& a, const int& b) {
    to = min(a, b);
}

void mx(int& to, const int& a, const int& b) {
    to = max(a, b);
}

struct segment {
    int v, l, r;
};

bool cmp (const segment& a, const segment& b) {
    if (a.l < b.l) {
        return true;
    }
    if (a.l > b.l) {
        return false;
    }
    return a.r < b.r;
}

bool operator < (const segment& a, const segment& b) {
    if (a.v < b.v) {
        return true;
    }
    if (a.v > b.v) {
        return false;
    }
    if (a.l < b.l) {
        return true;
    }
    if (a.l > b.l) {
        return false;
    }
    return a.r < b.r;
}

mt19937_64 mt(418);

void solve();
void init();

int32_t main() {
#ifndef LOCAL
    cin.tie(nullptr)->sync_with_stdio(false);
#endif
    // srand(time(0));
    init();
    cout << fixed << setprecision(20);
    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }
}

const int N = 100100, Q = 50500, M = 200200, LG = 18;
segment_tree_default<int> stl[LG], str[LG];
int a[M], b[M], szl, szr;
vector<int> start_l[N], start_r[N], end_l[N], end_r[N];
segment seg_l[M], seg_r[M];
set<segment> nwl, nwr;

void init() {
    for (int i = 0; i < LG; i++) {
        stl[i] = segment_tree_default<int>(N, mn, INT32_MAX);
        str[i] = segment_tree_default<int>(N, mx, INT32_MIN);
    }
}

void solve() {
    int n, k, m;
    cin >> n >> k >> m;
    for (int i = 0; i < m; i++) {
        cin >> a[i] >> b[i]; a[i]--; b[i]--;
    }
    for (int i = 0; i < m; i++) {
        if (a[i] < b[i]) {
            start_r[a[i]].push_back(szr);
            end_r[min(b[i], a[i] + k - 1)].push_back(szr);
            seg_r[szr++] = {-b[i], a[i], min(b[i], a[i] + k - 1)};
        } else {
            start_l[max(b[i], a[i] - k + 1)].push_back(szl);
            end_l[a[i]].push_back(szl);
            seg_l[szl++] = {b[i], max(b[i], a[i] - k + 1), a[i]};
        }
    }
    nwl.insert({n, 0, 0});
    nwr.insert({1, 0, 0});
    for (int i = 0; i < n; i++) {
        for (int j : start_l[i]) {
            nwl.insert(seg_l[j]);
        }
        // cout << min((*nwl.begin()).v, i) << ' ';
        stl[0].update_element(i, min((*nwl.begin()).v, i));
        for (int j : end_l[i]) {
            nwl.erase(seg_l[j]);
        }
    }
    // cout << '\n';
    for (int i = 0; i < n; i++) {
        for (int j : start_r[i]) {
            nwr.insert(seg_r[j]);
        }
        // cout << max(-(*nwr.begin()).v, i) << ' ';
        str[0].update_element(i, max(-(*nwr.begin()).v, i));
        for (int j : end_r[i]) {
            nwr.erase(seg_r[j]);
        }
    }
    // cout << '\n';
    for (int l = 1; l < LG; l++) {
        for (int i = 0; i < n; i++) {
            stl[l].update_element(i, stl[l - 1].get(stl[l - 1].get(i, i), str[l - 1].get(i, i)));
            str[l].update_element(i, str[l - 1].get(stl[l - 1].get(i, i), str[l - 1].get(i, i)));
        }
    }
    int q;
    cin >> q;
    while (q--) {
        int l, r;
        cin >> l >> r; l--; r--;
        int nw = 0, left = l, right = l;
        for (int i = LG - 1; i >= 0; i--) {
            int new_l = stl[i].get(left, right), new_r = str[i].get(left, right);
            if (r > new_r || r < new_l) {
                left = new_l;
                right = new_r;
                nw += 1 << i;
            }
        }
        int new_l = stl[0].get(left, right), new_r = str[0].get(left, right);
        // cout << nw << ' ' << new_l << ' ' << new_r << '\n';
        nw++;
        if (new_l <= r && r <= new_r) {
            cout << nw << '\n';
        } else {
            cout << "-1\n";
        }
    }
}

Compilation message (stderr)

Main.cpp: In instantiation of 'segment_tree_default<T>::segment_tree_default(int, void (*)(T&, const T&, const T&), T) [with T = int]':
Main.cpp:143:60:   required from here
Main.cpp:31:21: warning: comparison of integer expressions of different signedness: 'size_t' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   31 |         while (size < n) {
      |                ~~~~~^~~

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 0 / 11
• Subtask 4: 0 / 25
• Subtask 5: 0 / 35
• Subtask 6: 0 / 13