Submission #242952

#	Time	Username	Problem	Language	Result	Execution time	Memory
242952		dung11112003	Jousting tournament (IOI12_tournament)	C++11	100 / 100	178 ms	12444 KiB

tournament

#include <bits/stdc++.h>

#define taskname ""
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define for0(i, n) for (int i = 0; i < (int)(n); ++i)
#define for1(i, n) for (int i = 1; i <= (int)(n); ++i)
#define ford(i, n) for (int i = (int)(n) - 1; i >= 0; --i)
#define fore(i, a, b) for (int i = (int)(a); i <= (int)(b); ++i)

using namespace std;

typedef long long ll;
typedef long double ld;
typedef complex <ld> cd;
typedef vector <cd> vcd;
typedef vector <int> vi;

template<class T> using v2d = vector <vector <T> >;
template<class T> bool uin(T &a, T b)
{
    return a > b ? (a = b, true) : false;
}
template<class T> bool uax(T &a, T b)
{
    return a < b ? (a = b, true) : false;
}

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

namespace firstSub
{
    list <int> a;
    int solve(int n, int m, int val, int *K, int *S, int *E)
    {
        int r = 0, p;
        for0(pos, n)
        {
            a.clear();
            for0(i, pos)
            {
                a.insert(a.end(), K[i]);
            }
            a.insert(a.end(), val);
            for (int i = pos; i < n; i++)
            {
                a.insert(a.end(), K[i]);
            }
            int cnt = 0;
            for0(i, m)
            {
                auto it = a.begin();
                advance(it, S[i]);
                int winner = 0;
                bool joined = 0;
                for (int j = S[i]; j <= E[i]; j++)
                {
                    uax(winner, *it);
                    joined |= (*it == val);
                    it++;
                }
                if (joined)
                {
                    if (winner == val)
                    {
                        ++cnt;
                    }
                    else
                    {
                        break;
                    }
                }
                it = a.begin();
                advance(it, S[i]);
                for (int j = S[i]; j <= E[i]; j++)
                {
                    if (*it < winner)
                    {
                        it = a.erase(it);
                    }
                    else
                    {
                        it++;
                    }
                }
            }
            if (uax(r, cnt))
            {
                p = pos;
            }
        }
        return p;
    }
}

namespace secondSub
{
    const int maxN = 5e3 + 10;

    int f[maxN * 4], L, R, val, d[maxN][20];
    bool lazy[maxN * 4];

    void build(int x, int lo, int hi)
    {
        if (lo == hi)
        {
            f[x] = 1;
            return;
        }
        int mid = (lo + hi) / 2;
        build(x * 2, lo, mid);
        build(x * 2 + 1, mid + 1, hi);
        f[x] = f[x * 2] + f[x * 2 + 1];
    }

    void down(int x)
    {
        bool d = lazy[x];
        if (d)
        {
            lazy[x] = 0;
            lazy[x * 2] = lazy[x * 2 + 1] = 1;
            f[x * 2] = f[x * 2 + 1] = 0;
        }
    }

    void update(int x, int lo, int hi)
    {
        if (lo > R || hi < L)
        {
            return;
        }
        if (lo >= L && hi <= R)
        {
            f[x] = 0;
            lazy[x] = 1;
            return;
        }
        down(x);
        int mid = (lo + hi) / 2;
        update(x * 2, lo, mid);
        update(x * 2 + 1, mid + 1, hi);
        f[x] = f[x * 2] + f[x * 2 + 1];
    }

    int query(int l, int r)
    {
        int h = 31 - __builtin_clz(r - l + 1);
        return max(d[l][h], d[r - (1 << h) + 1][h]);
    }

    void recal(int n, int idx, int val)
    {
        d[idx][0] = val;
        for (int j = 1; (1 << j) <= n; j++)
        {
            for (int i = idx; i + (1 << j) - 1 >= idx && i >= 0; i--)
            {
                if (i + (1 << j) - 1 < n)
                {
                    d[i][j] = max(d[i][j - 1], d[i + (1 << (j - 1))][j - 1]);
                }
            }
        }
    }

    int findPos(int x, int lo, int hi, int sum)
    {
        if (val <= 0)
        {
            return -1;
        }
        if (lo == hi)
        {
            return lo;
        }
        down(x);
        int mid = (lo + hi) / 2;
        if (f[x * 2] + sum >= val)
        {
            return findPos(x * 2, lo, mid, sum);
        }
        return findPos(x * 2 + 1, mid + 1, hi, sum + f[x * 2]);
    }

    int solve(int n, int m, int target, int *K, int *S, int *E)
    {
        vector <int> l(m), r(m);
        build(1, 0, n - 1);
        for0(i, m)
        {
            val = E[i] + 1;
            r[i] = findPos(1, 0, n - 1, 0);
            val = S[i];
            l[i] = findPos(1, 0, n - 1, 0) + 1;
            L = l[i], R = r[i] - 1;
            update(1, 0, n - 1);
        }
        int ans = -1, p;
        d[0][0] = target;
        for0(i, n - 1)
        {
            d[i + 1][0] = K[i];
        }
        for (int j = 1; (1 << j) <= n; j++)
        {
            for (int i = 0; i + (1 << j) - 1 < n; i++)
            {
                d[i][j] = max(d[i][j - 1], d[i + (1 << (j - 1))][j - 1]);
            }
        }
        for0(pos, n)
        {
            int cnt = 0;
            for0(i, m)
            {
                if (l[i] > pos || r[i] < pos)
                {
                    continue;
                }
                cnt += query(l[i], r[i]) == target;
            }
            if (pos < n - 1)
            {
                recal(n, pos, K[pos]);
                recal(n, pos + 1, target);
            }
            if (uax(ans, cnt))
            {
                p = pos;
            }
        }
        return p;
    }
}

namespace fullSub
{
    const int maxN = 1e5 + 10;

    int f[maxN * 4], g[maxN * 4], L, R, idx, val;
    bool lazy[maxN * 4];

    void build(int x, int lo, int hi)
    {
        if (lo == hi)
        {
            f[x] = 1;
            return;
        }
        int mid = (lo + hi) / 2;
        build(x * 2, lo, mid);
        build(x * 2 + 1, mid + 1, hi);
        f[x] = f[x * 2] + f[x * 2 + 1];
    }

    void down(int x)
    {
        bool d = lazy[x];
        if (d)
        {
            lazy[x] = 0;
            lazy[x * 2] = lazy[x * 2 + 1] = 1;
            f[x * 2] = f[x * 2 + 1] = 0;
        }
    }

    void update(int x, int lo, int hi)
    {
        if (lo > R || hi < L)
        {
            return;
        }
        if (lo >= L && hi <= R)
        {
            f[x] = 0;
            lazy[x] = 1;
            return;
        }
        down(x);
        int mid = (lo + hi) / 2;
        update(x * 2, lo, mid);
        update(x * 2 + 1, mid + 1, hi);
        f[x] = f[x * 2] + f[x * 2 + 1];
    }

    void modify(int x, int lo, int hi)
    {
        if (lo == hi && lo == idx)
        {
            g[x] = val;
            return;
        }
        int mid = (lo + hi) / 2;
        if (idx <= mid)
        {
            modify(x * 2, lo, mid);
        }
        else
        {
            modify(x * 2 + 1, mid + 1, hi);
        }
        g[x] = max(g[x * 2], g[x * 2 + 1]);
    }

    int query(int x, int lo, int hi)
    {
        if (lo > R || hi < L)
        {
            return 0;
        }
        if (lo >= L && hi <= R)
        {
            return g[x];
        }
        int mid = (lo + hi) / 2;
        return max(query(x * 2, lo, mid), query(x * 2 + 1, mid + 1, hi));
    }

    int findPos(int x, int lo, int hi, int sum)
    {
        if (val <= 0)
        {
            return -1;
        }
        if (lo == hi)
        {
            return lo;
        }
        down(x);
        int mid = (lo + hi) / 2;
        if (f[x * 2] + sum >= val)
        {
            return findPos(x * 2, lo, mid, sum);
        }
        return findPos(x * 2 + 1, mid + 1, hi, sum + f[x * 2]);
    }

    int solve(int n, int m, int target, int *K, int *S, int *E)
    {
        vector <int> l(m), r(m);
        build(1, 0, n - 1);
        for0(i, m)
        {
            val = E[i] + 1;
            r[i] = findPos(1, 0, n - 1, 0);
            val = S[i];
            l[i] = findPos(1, 0, n - 1, 0) + 1;
            L = l[i], R = r[i] - 1;
            update(1, 0, n - 1);
        }
        vector <vector <int>> start(n), finish(n);
        for0(i, m)
        {
            start[l[i]].eb(i);
            finish[r[i]].eb(i);
        }
        int ans = -1, p, cnt = 0;
        idx = 0, val = target;
        modify(1, 0, n - 1);
        for0(i, n - 1)
        {
            idx = i + 1, val = K[i];
            modify(1, 0, n - 1);
        }
        for0(i, m)
        {
            if (l[i] <= 0 && r[i] >= 0)
            {
                L = l[i], R = r[i];
                cnt += (query(1, 0, n - 1) == target);
            }
        }
        if (uax(ans, cnt))
        {
            p = 0;
        }
        fore(pos, 1, n - 1)
        {
            for (auto &id: finish[pos - 1])
            {
                L = l[id], R = r[id];;
                cnt -= (query(1, 0, n - 1) == target);
            }
            idx = pos - 1, val = K[pos - 1];
            modify(1, 0, n - 1);
            idx = pos, val = target;
            modify(1, 0, n - 1);
            for (auto &id: start[pos])
            {
                L = l[id], R = r[id];
                cnt += (query(1, 0, n - 1) == target);
            }
            if (uax(ans, cnt))
            {
                p = pos;
            }
        }
        return p;
    }
}

int GetBestPosition(int n, int m, int val, int *K, int *S, int *E)
{
    if (n <= 500)
    {
        return firstSub::solve(n, m, val, K, S, E);
    }
    else if (n <= 5000)
    {
        return secondSub::solve(n, m, val, K, S, E);
    }
    else
    {
        return fullSub::solve(n, m, val, K, S, E);
    }
}

Compilation message (stderr)

tournament.cpp: In function 'int secondSub::solve(int, int, int, int*, int*, int*)':
tournament.cpp:237:16: warning: 'p' may be used uninitialized in this function [-Wmaybe-uninitialized]
         return p;
                ^
tournament.cpp: In function 'int firstSub::solve(int, int, int, int*, int*, int*)':
tournament.cpp:96:16: warning: 'p' may be used uninitialized in this function [-Wmaybe-uninitialized]
         return p;
                ^

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