Submission #962360

#	Time	Username	Problem	Language	Result	Execution time	Memory
962360		GrindMachine	Jousting tournament (IOI12_tournament)	C++17	49 / 100	1031 ms	6352 KiB

tournament

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

template<typename T>
struct segtree {
    // https://codeforces.com/blog/entry/18051

    /*=======================================================*/

    struct data {
        int mnl,mxr,cnt;
    };

    data neutral = {inf1,-inf1,0};

    data merge(data &left, data &right) {
        data curr;

        curr.mnl = min(left.mnl,right.mnl);
        curr.mxr = max(left.mxr,right.mxr);
        curr.cnt = left.cnt+right.cnt;
        
        return curr;
    }

    void create(int i, T v) {

    }

    void modify(int i, T v) {
        tr[i].mnl = v.ff, tr[i].mxr = v.ss;
        tr[i].cnt = (v.ff != inf1);
    }

    /*=======================================================*/

    int n;
    vector<data> tr;

    segtree() {

    }

    segtree(int siz) {
        init(siz);
    }

    void init(int siz) {
        n = siz;
        tr.assign(2 * n, neutral);
    }

    void build(vector<T> &a, int siz) {
        rep(i, siz) create(i + n, a[i]);
        rev(i, n - 1, 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
    }

    void pupd(int i, T v) {
        modify(i + n, v);
        for (i = (i + n) >> 1; i; i >>= 1) tr[i] = merge(tr[i << 1], tr[i << 1 | 1]);
    }

    data query(int l, int r) {
        data resl = neutral, resr = neutral;

        for (l += n, r += n; l <= r; l >>= 1, r >>= 1) {
            if (l & 1) resl = merge(resl, tr[l++]);
            if (!(r & 1)) resr = merge(tr[r--], resr);
        }

        return merge(resl, resr);
    }
};

int GetBestPosition(int n, int m, int R, int *a, int *S, int *E) {
    Tree<pii> os;
    rep(i,n) os.insert({i,i});

    rep(i,m){
        int l = S[i], r = E[i];
        int times = r-l;
        auto it = os.find_by_order(l);
        auto pl = *it;
        vector<pii> torem;
        torem.pb(pl);
        while(times--){
            it++;
            torem.pb(*it);
        }
        auto pr = *it;

        trav(px,torem) os.erase(px);
        os.insert({pl.ff,pr.ss});

        S[i] = pl.ff, E[i] = pr.ss;
    }

    assert(sz(os) == 1);
    assert(S[m-1] == 0 and E[m-1] == n-1);

    vector<int> enter[n+5], leave[n+5];
    rep(i,m){
        int l = S[i], r = E[i];
        enter[l].pb(i), leave[r+1].pb(i);
    }

    vector<int> nxt_big(n,n);
    rev(i,n-2,0){
        if(a[i] > R) nxt_big[i] = i;
        else nxt_big[i] = nxt_big[i+1];
    }

    segtree<pii> st(m+5);
    int best = -1;
    int ans = -1;
    int pbig = -1;

    rep(i,n){
        trav(id,enter[i]){
            int l = S[id], r = E[id];
            st.pupd(id,{l,r});
        }

        trav(id,leave[i]){
            st.pupd(id,{inf1,-inf1});
        }

        // l >= lx, r <= rx
        int lx = pbig+1;
        int rx = nxt_big[i];
        int cnt = 0;

        rep(id,m){
            int l = S[id], r = E[id];
            if(r < i or l > i) conts;
            bool ok = true;
            for(int j = l; j <= r-1; ++j){
                if(a[j] > R){
                    ok = false;
                }
            }

            if(ok) cnt++;
            else break;
        }

        if(cnt > best){
            best = cnt;
            ans = i;
        }

        // int lo = 0, hi = m-1;
        // int mx_good = -1;

        // while(lo <= hi){
        //     int mid = (lo+hi) >> 1;
        //     auto [l,r,cnt] = st.query(0,mid);
        //     if(l >= lx and r <= rx){
        //         mx_good = mid;
        //         lo = mid+1;
        //     }
        //     else{
        //         hi = mid-1;
        //     }
        // }

        // int val = st.query(0,mx_good).cnt;
        // amax(ans,val);

        // if(i < n-1 and a[i] > R) pbig = i;
    }

    return ans;
}

Compilation message (stderr)

tournament.cpp: In function 'int GetBestPosition(int, int, int, int*, int*, int*)':
tournament.cpp:185:13: warning: unused variable 'lx' [-Wunused-variable]
  185 |         int lx = pbig+1;
      |             ^~
tournament.cpp:186:13: warning: unused variable 'rx' [-Wunused-variable]
  186 |         int rx = nxt_big[i];
      |             ^~

• Subtask 1: 17 / 17
• Subtask 2: 32 / 32
• Subtask 3: 0 / 51