Submission #569326

#	Time	Username	Problem	Language	Result	Execution time	Memory
569326		ngpin04	Seats (IOI18_seats)	C++17	37 / 100	2474 ms	257020 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;

pair <int, int> st[N << 2];

int lz[N << 2];

set <int> sr[N], sc[N];

int minx[N];
int miny[N];
int maxx[N];
int maxy[N];
int x[N];
int y[N];
int a[N];
int n,m,sz,ans;

void dolazy(int id) {
    for (int i = (id << 1); i <= (id << 1 | 1); i++) {
        lz[i] += lz[id];
        st[i].fi += lz[id];
    }
}

void build(int id, int l, int r) {
    if (l == r) {
        st[id].se = 1;
        return;
    }
    int mid = (l + r) >> 1;
    build(id << 1, l, mid);
    build(id << 1 | 1, mid + 1, r);
}

void update(int id, int l, int r, int u, int v, int val) {
    if (l > v || r < u)
        return;
    if (l >= u && r <= v) {
        lz[id] += val;
        st[id].fi += val;
        return;
    }
    int mid = (l + r) >> 1;
    dolazy(id);
    update(id << 1, l, mid, u, v, val);
    update(id << 1 | 1, mid + 1, r, u, v, val);

    st[id] = st[id << 1];

    if (mini(st[id].fi, st[id << 1 | 1].fi))
        st[id] = st[id << 1 | 1];
    else if (st[id].fi == st[id << 1 | 1].fi)
        st[id].se += st[id << 1 | 1].se;
}   

void update(int l, int r, int val) {
    update(1, 0, sz - 1, l, r, val);
}

int getmin() {
    return st[1].se;
}

bool check(int i) {
    int dx = maxx[i] - minx[i] + 1;
    int dy = maxy[i] - miny[i] + 1;
    return (dx * dy == i + 1);
}

void give_initial_chart(int H, int W, vector<int> R, vector<int> C) {
    n = H;
    m = W;
    sz = n * m;
    build(1, 0, sz - 1);
    for (int i = 0; i < n * m; i++) {
        x[i] = R[i], y[i] = C[i];
        sr[x[i]].insert(i);
        sc[y[i]].insert(i);
        minx[i] = maxx[i] = x[i];
        miny[i] = maxy[i] = y[i];
        a[y[i]] = i;
    }

    for (int i = 0; i + 1 < n * m; i++) 
        update(max(a[i], a[i + 1]), sz - 1, -1);

    for (int i = 0; i < n * m; i++) {
        if (i > 0) {
            mini(minx[i], minx[i - 1]);
            mini(miny[i], miny[i - 1]);
            maxi(maxx[i], maxx[i - 1]);
            maxi(maxy[i], maxy[i - 1]);
        }
        ans += check(i);
    }

    for (int i = 0; i < sz; i++)
        update(i, i, i);
}

int sub2() {
    vector <int> events;
    for (int i = 0; i < n; i++) 
        events.push_back(*sr[i].begin());

    for (int i = 0; i < m; i++)
        events.push_back(*sc[i].begin());

    sort(ALL(events));

    int minx = oo, maxx = -oo, miny = oo, maxy = -oo;
    int res = 0;
    for (int it = 0; it < (int) events.size(); it++)  {
        if (it + 1 == (int) events.size()) {
            res++;
            break;
        }
        int i = events[it];
        int j = events[it + 1];
        mini(minx, x[i]);
        mini(miny, y[i]);
        maxi(maxx, x[i]);
        maxi(maxy, y[i]);
        int t = (maxx - minx + 1) * (maxy - miny + 1);
        res += (i <= t && t <= j);
    }
    return res;
}

int sub3(int l, int r) {
    if (l > r)
        swap(l, r);
    for (int i = l; i <= r; i++) {
        ans -= check(i);
        minx[i] = maxx[i] = x[i];
        miny[i] = maxy[i] = y[i];
        if (i > 0) {
            mini(minx[i], minx[i - 1]);
            mini(miny[i], miny[i - 1]);
            maxi(maxx[i], maxx[i - 1]);
            maxi(maxy[i], maxy[i - 1]);
        }
        ans += check(i);
    }
    return ans;
}

void add(int i, int val) {
    int pos = y[i];
    if (pos > 0) 
        update(max(a[pos - 1], a[pos]), sz - 1, val);
    if (pos + 1 < sz)
        update(max(a[pos], a[pos + 1]), sz - 1, val);
}

int sub4() {
    return getmin();
}

int swap_seats(int l, int r) {
    sr[x[l]].erase(l);
    sr[x[r]].erase(r);
    sc[y[l]].erase(l);
    sc[y[r]].erase(r);

    add(l, 1);
    add(r, 1);
    swap(x[l], x[r]);
    swap(y[l], y[r]);
    swap(a[y[l]], a[y[r]]);

    add(l, -1);
    add(r, -1);
    sr[x[l]].insert(l);
    sr[x[r]].insert(r);
    sc[y[l]].insert(l);
    sc[y[r]].insert(r);

    if (max(n, m) <= 1000)
        return sub2();
    if (abs(l - r) <= 10000)
        return sub3(l, r);
    if (n == 1)
        return sub4();
    return -1;
}

//#include "grader.cpp"   

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