Submission #569292

#	Time	Username	Problem	Language	Result	Execution time	Memory
569292		ngpin04	Seats (IOI18_seats)	C++17	31 / 100	2992 ms	227660 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 st[N << 2];

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

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

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];
        sr[x[i]].insert(i);
        sc[y[i]].insert(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() {
    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 swap_seats(int a, int b) {
    sr[x[a]].erase(a);
    sr[x[b]].erase(b);
    sc[y[a]].erase(a);
    sc[y[b]].erase(b);
    swap(x[a], x[b]);
    swap(y[a], y[b]);

    sr[x[a]].insert(a);
    sr[x[b]].insert(b);
    sc[y[a]].insert(a);
    sc[y[b]].insert(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: 20 / 20
• Subtask 4: 0 / 6
• Subtask 5: 0 / 33
• Subtask 6: 0 / 30