Submission #569290

#	Time	Username	Problem	Language	Result	Execution time	Memory
569290		ngpin04	Seats (IOI18_seats)	C++17	11 / 100	4038 ms	57692 KiB

seats

#include "seats.h"
#include <bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define TASK ""
#define bit(x) (1LL << (x))
#define getbit(x, i) (((x) >> (i)) & 1)
#define ALL(x) (x).begin(), (x).end() 
using namespace std;
template <typename T1, typename T2> bool mini(T1 &a, T2 b) {
    if (a > b) {a = b; return true;} return false;
}
template <typename T1, typename T2> bool maxi(T1 &a, T2 b) {
    if (a < b) {a = b; return true;} return false;
}
mt19937_64 rd(chrono::steady_clock::now().time_since_epoch().count());

int rand(int l, int r) {
    return l + rd() % (r - l + 1);
}
const int N = 1e6 + 5; 
const int oo = 1e9;
const long long ooo = 1e18;
const int mod = 1e9 + 7; // 998244353;
const long double pi = acos(-1);

typedef tuple <int, int, int, int> pir;

pir add(pir a, pir b) {
    auto [minx1, maxx1, miny1, maxy1] = a;
    auto [minx2, maxx2, miny2, maxy2] = b;
    return {
        min(minx1, minx2), 
        max(maxx1, maxx2),
        min(miny1, miny2),
        max(maxy1, maxy2)
    };
}

pir st[N << 2];

int x[N];
int y[N];
int n,m,sz;

void update(int id, int l, int r, int pos, int x, int y) {
    if (l > pos || r < pos)
        return;
    if (l == r) {
        st[id] = {x, x, y, y};
        return;
    }
    int mid = (l + r) >> 1;
    update(id << 1, l, mid, pos, x, y);
    update(id << 1 | 1, mid + 1, r, pos, x, y);
    st[id] = add(st[id << 1], st[id << 1 | 1]);
}

void update(int pos, int x, int y) {
    update(1, 0, sz - 1, pos, x, y);
}

pir getval(int id, int l, int r, int u, int v) {
    if (l > v || r < u)
        return {oo, -oo, oo, -oo};
    if (l >= u && r <= v) 
        return st[id];
    int mid = (l + r) >> 1;
    auto lnode = getval(id << 1, l, mid, u, v);
    auto rnode = getval(id << 1 | 1, mid + 1, r, u, v);
    return add(lnode, rnode);
}

pir getval(int l, int r) {
    return getval(1, 0, sz - 1, l, r);
}

void give_initial_chart(int H, int W, vector<int> R, vector<int> C) {
    n = H;
    m = W;
    sz = n * m;
    for (int i = 0; i < n * m; i++) {
        x[i] = R[i], y[i] = C[i];
        update(i, x[i], y[i]);
    }
}

int brute() {
    int ans = 0;
    int minx = oo, miny = oo, maxx = -oo, maxy = -oo;
    for (int i = 0; i < n * m; i++) {
        mini(minx, x[i]);
        maxi(maxx, x[i]);
        mini(miny, y[i]);
        maxi(maxy, y[i]);
        int dx = maxx - minx + 1;
        int dy = maxy - miny + 1;
        ans += (dx * dy == i + 1);
    }
    return ans;
}   

int sub2() {
    int res = 1;
    pair <int, int> rx = {x[0], x[0]}, ry{y[0], y[0]};

    int cur = 0;
    while (cur < n * m - 1) {
        int dx = rx.se - rx.fi + 1;
        int dy = ry.se - ry.fi + 1;
        // cerr << cur << " " << dx << " " << dy << "\n";
        int cnt = dx * dy;
        int t = 0;
        if (cnt == cur + 1) {
            int d = oo;
            mini(d, (dx == n) ? dx : dy);
            mini(d, (dy == m) ? dy : dx);
            t = cur + d;
            res++;
        } else {
            t = cnt - 1;
        }

        cur = t;
        auto [l, r, u, v] = getval(0, t);
        rx = {l, r};
        ry = {u, v};
    }
    return res;
}

int swap_seats(int a, int b) {
    swap(x[a], x[b]);
    swap(y[a], y[b]);
    update(a, x[a], y[a]);
    update(b, x[b], y[b]);
    if (n * m <= 10000)
        return brute();
    if (max(n, m) <= 1000)
        return sub2();
    return -1;
}

//#include "grader.cpp"   

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