Submission #571510

#	Time	Username	Problem	Language	Result	Execution time	Memory
571510		elazarkoren	Seats (IOI18_seats)	C++17	25 / 100	4104 ms	73588 KiB

seats

#include <bits/stdc++.h>
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define chkmin(a, b) a = min(a, b)
#define chkmax(a, b) a = max(a, b)
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> pii;
typedef vector<pii> vii;

const int MAX_N = 1e6 + 5;

struct Seg {
    int n;
    vii seg;
    Seg() {}
    Seg(int m) {
        for (n = 1; n < m; n <<= 1);
        seg.resize(2 * n);
    }
    void update(int i, int x) {
        seg[i += n] = {x, x};
        for (i >>= 1; i; i >>= 1) {
            seg[i].x = min(seg[i << 1].x, seg[i << 1 | 1].x);
            seg[i].y = max(seg[i << 1].y, seg[i << 1 | 1].y);
        }
    }
    pii query(int l, int r) {
        pii ans = {MAX_N, 0};
        for (l += n, r += n; l < r; l >>= 1, r >>= 1) {
            if (l & 1) {
                chkmin(ans.x, seg[l].x);
                chkmax(ans.y, seg[l].y);
                l++;
            }
            if (r & 1) {
                --r;
                chkmin(ans.x, seg[r].x);
                chkmax(ans.y, seg[r].y);
            }
        }
        return ans;
    }
};

int r[MAX_N], c[MAX_N];
Seg r_seg, c_seg;
int n;
int h, w;

inline void update(int i) {
    r_seg.update(i, r[i]);
    c_seg.update(i, c[i]);
}

void give_initial_chart(int H, int W, std::vector<int> R, std::vector<int> C) {
    h = H, w = W;
    n = h * w;
    r_seg = c_seg = Seg(n);
    for (int i = 0; i < n; i++) {
        r[i] = R[i], c[i] = C[i];
        update(i);
    }
}

int swap_seats(int a, int b) {
    swap(r[a], r[b]), swap(c[a], c[b]);
    update(a), update(b);
    int ans = 0;
    for (int i = 0; i < n; i++) {
        auto [x1, x2] = r_seg.query(0, i + 1);
        auto [y1, y2] = c_seg.query(0, i + 1);
        if ((x2 - x1 + 1) * (y2 - y1 + 1) == i + 1) {
            ans++;
        } else {
            i = (x2 - x1 + 1) * (y2 - y1 + 1) - 2;
        }
    }
    return ans;
}
//2 3 2
//0 0
//1 0
//1 1
//0 1
//0 2
//1 2
//0 5
//0 5

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