Submission #591357

#	Time	Username	Problem	Language	Result	Execution time	Memory
591357		cheissmart	Jousting tournament (IOI12_tournament)	C++14	100 / 100	198 ms	48332 KiB

tournament

#include <bits/stdc++.h>
#define IO_OP ios::sync_with_stdio(0), cin.tie(0)
#define F first
#define S second
#define V vector
#define PB push_back
#define EB emplace_back
#define MP make_pair
#define SZ(v) int((v).size())
#define ALL(v) (v).begin(), (v).end()

using namespace std;

typedef long long ll;
typedef pair<int, int> pi;
typedef V<int> vi;

const int INF = 1e9 + 7, N = 5e5 + 7;

int n, m, k;
int *a, *l, *r;

struct node {
    int sum, lz;
    node() { lz = -1; }
} t[N * 4];


void apply(int v, int x, int tl, int tr) {
    t[v].sum = x * (tr - tl);
    t[v].lz = x;
}

void push(int v, int tl, int tr) {
    if(t[v].lz != -1) {
        int tm = (tl + tr) / 2;
        apply(v * 2, t[v].lz, tl, tm);
        apply(v * 2 + 1, t[v].lz, tm, tr);
        t[v].lz = -1;
    }
}

void pull(int v) {
    t[v].sum = t[v * 2].sum + t[v * 2 + 1].sum;
}

void build(int v = 1, int tl = 0, int tr = n + 1) {
    if(tr - tl == 1) {
        apply(v, 1, tl, tr);
        return;
    }
    int tm = (tl + tr) / 2;
    build(v * 2, tl, tm);
    build(v * 2 + 1, tm, tr);
    pull(v);
}

void upd(int l, int r, int x, int v = 1, int tl = 0, int tr = n + 1) {
    if(l <= tl && tr <= r) {
        apply(v, x, tl, tr);
        return;
    }
    push(v, tl, tr);
    int tm = (tl + tr) / 2;
    if(l < tm) upd(l, r, x, v * 2, tl, tm);
    if(r > tm) upd(l, r, x, v * 2 + 1, tm, tr);
    pull(v);
}

int get_first(int x, int v = 1, int tl = 0, int tr = n + 1) {
    assert(x && t[v].sum >= x);
    if(tr - tl == 1) return tl;
    push(v, tl, tr);
    int tm = (tl + tr) / 2;
    if(t[v * 2].sum >= x) {
        return get_first(x, v * 2, tl, tm);
    } else {
        return get_first(x - t[v * 2].sum, v * 2 + 1, tm, tr);
    }
}

int st[N][20];
int p[N][20];

int GetBestPosition(int _n, int _m, int _k, int *_a, int *_l, int *_r) {
    n = _n, m = _m, k = _k, a = _a, l = _l, r = _r;

    build();

    for(int i = 0; i < n - 1; i++)
        st[i][0] = a[i];
    for(int j = 1; j < 20; j++)
        for(int i = 0; i + (1 << j) - 1 < n - 1; i++)
            st[i][j] = max(st[i][j - 1], st[i + (1 << (j - 1))][j - 1]);

    auto qry_mx = [&] (int l, int r) { // [l, r]
        assert(0 <= l && l <= r && r < n - 1);
        int k = __lg(r - l + 1);
        return max(st[l][k], st[r - (1 << k) + 1][k]);
    };

    V<array<int, 3>> ev;

    for(int i = 0; i < n; i++) {
        ev.PB({i, 1, -i});
        ev.PB({i + 1, -1, i});
    }
    V<pi> tt;
    for(int i = 0; i < m; i++) {
        int L = get_first(l[i] + 1);
        int R = get_first(r[i] + 2);
        // [L, R)
        upd(L, R, 0);
        upd(L, L + 1, 1);
        ev.PB({L, 1, -(i + n)});
        ev.PB({R, -1, (i + n)});
        tt.EB(L, R);
    }
    sort(ALL(ev));
    p[abs(ev[0][2])][0] = -1;
    for(int i = 1; i < SZ(ev); i++) {
        if(ev[i][1] == 1) { // L
            if(ev[i - 1][1] == 1) {
                p[abs(ev[i][2])][0] = abs(ev[i - 1][2]);
            } else {
                p[abs(ev[i][2])][0] = p[abs(ev[i - 1][2])][0];
            }
        }
    }

    for(int j = 1; j < 20; j++)
        for(int i = 0; i < n + m; i++) {
            p[i][j] = -1;
            if(p[i][j - 1] != -1)
                p[i][j] = p[p[i][j - 1]][j - 1];
        }

    int best_pos = -1, mx = -1;

    for(int i = 0; i < n; i++) {
        int cur = 0, u = i;
        for(int j = 19; j >= 0; j--) {
            if(p[u][j] != -1 && qry_mx(tt[p[u][j] - n].F, tt[p[u][j] - n].S - 2) < k) {
                u = p[u][j];
                cur += 1 << j;
            }
        }
        if(cur > mx) {
            mx = cur;
            best_pos = i;
        }
    }

    return best_pos;

}

• Subtask 1: 17 / 17
• Subtask 2: 32 / 32
• Subtask 3: 51 / 51