Submission #763153

#	Time	Username	Problem	Language	Result	Execution time	Memory
763153		t6twotwo	Seats (IOI18_seats)	C++17	17 / 100	4006 ms	88244 KiB

seats

#include "seats.h"
#include <bits/stdc++.h>
using namespace std;
constexpr int inf = 6 << 22;
template <typename T>
struct segment_tree {
    int n;
    vector<T> s;
    segment_tree() {
    }
    segment_tree(int _n) {
        n = 2 << __lg(_n);
        s.resize(2 * n - 1);
    }
    segment_tree(vector<T> &a) : segment_tree(a.size()) {
        for (int i = 0; i < a.size(); i++) {
            s[i + n - 1] = a[i];
        }
        for (int i = n - 2; i >= 0; i--) {
            s[i] = s[i * 2 + 1] + s[i * 2 + 2];
        }
    }
    void modify(int p, int l, int r, int x, const T &v) {
        if (l + 1 == r) {
            s[p] = v;
            return;
        }
        int m = (l + r + 1) / 2;
        if (x < m) {
            modify(p * 2 + 1, l, m, x, v);
        } else {
            modify(p * 2 + 2, m, r, x, v);
        }
        s[p] = s[p * 2 + 1] + s[p * 2 + 2];
    }
    void modify(int x, const T &v) {
        modify(0, 0, n, x, v);
    }
    T range_query(int p, int l, int r, int L, int R) {
        if (R <= l || r <= L) {
            return T();
        }
        if (L <= l && r <= R) {
            return s[p];
        }
        int m = (l + r + 1) / 2;
        return range_query(p * 2 + 1, l, m, L, R) + range_query(p * 2 + 2, m, r, L, R);
    }
    T range_query(int l, int r) {
        return range_query(0, 0, n, l, r);
    }
};
struct node {
    int xmin, xmax, ymin, ymax;
    node() {
        xmin = inf;
        xmax = -inf;
        ymin = inf;
        ymax = -inf;
    }
    node(int a, int b, int c, int d) {
        xmin = a;
        xmax = b;
        ymin = c;
        ymax = d;
    }
};
node operator+(node a, node b) {
    node c;
    c.xmin = min(a.xmin, b.xmin);
    c.xmax = max(a.xmax, b.xmax);
    c.ymin = min(a.ymin, b.ymin);
    c.ymax = max(a.ymax, b.ymax);
    return c;
}
int N, M, ans, T;
vector<int> A, B, xmax, xmin, ymax, ymin;
int f(int k) {
    return (xmax[k] - xmin[k] + 1) * (ymax[k] - ymin[k] + 1) == k;
}
segment_tree<node> st;
void give_initial_chart(int H, int W, std::vector<int> R, std::vector<int> C) {
    N = H, M = W;
    A = R, B = C;
    xmax.resize(N * M + 1, -1);
    xmin.resize(N * M + 1, N);
    ymax.resize(N * M + 1, -1);
    ymin.resize(N * M + 1, M);
    for (int i = 0; i < N * M; i++) {
        xmax[i + 1] = max(xmax[i], A[i]);
        xmin[i + 1] = min(xmin[i], A[i]);
        ymax[i + 1] = max(ymax[i], B[i]);
        ymin[i + 1] = min(ymin[i], B[i]);
        ans += f(i + 1);
    }
    vector<node> t(N * M);
    for (int i = 0; i < N * M; i++) {
        t[i] = {A[i], A[i], B[i], B[i]};
    }
    st = segment_tree<node>(t);
}
int swap_seats(int a, int b) {
    swap(A[a], A[b]);
    swap(B[a], B[b]);
    if (abs(a - b) <= 100000) {
        for (int i = min(a, b); i <= max(a, b); i++) {
            ans -= f(i + 1);
            xmax[i + 1] = max(xmax[i], A[i]);
            xmin[i + 1] = min(xmin[i], A[i]);
            ymax[i + 1] = max(ymax[i], B[i]);
            ymin[i + 1] = min(ymin[i], B[i]);
            ans += f(i + 1);
        }
        return ans;
    }
    int ans = 1;
    st.modify(a, {A[a], A[a], B[a], B[a]});
    st.modify(b, {A[b], A[b], B[b], B[b]});
    int s = 0, L = B[0], R = B[0], U = A[0], D = A[0];
    while (L != 0 || R != M - 1 || U != 0 || D != N - 1) {
        int lo = s + 1, hi = N * M - 1;
        while (lo < hi) {
            int mi = (lo + hi) / 2;
            node t = st.range_query(s + 1, mi + 1);
            if (t.xmin < U || t.xmax > D || t.ymin < L || t.ymax > R) {
                hi = mi;
            } else {
                lo = mi + 1;
            }
        }
        if ((D - U + 1) * (R - L + 1) == lo) {
            ans++;
        }
        U = min(U, A[lo]);
        D = max(D, A[lo]);
        L = min(L, B[lo]);
        R = max(R, B[lo]);
        s = lo;
    }
    return ans;
}

Compilation message (stderr)

seats.cpp: In instantiation of 'segment_tree<T>::segment_tree(std::vector<_Tp>&) [with T = node]':
seats.cpp:100:30:   required from here
seats.cpp:16:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<node, std::allocator<node> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |         for (int i = 0; i < a.size(); i++) {
      |                         ~~^~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 0 / 20
• Subtask 4: 6 / 6
• Subtask 5: 0 / 33
• Subtask 6: 0 / 30