Submission #1084009

#	Time	Username	Problem	Language	Result	Execution time	Memory
1084009		Tymond	Arranging Shoes (IOI19_shoes)	C++17	100 / 100	144 ms	67620 KiB

shoes

#include <bits/stdc++.h>
#include "shoes.h"
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::steady_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

const int BASE = (1 << 19);
int tree[2 * BASE + 7];
int tree2[2 * BASE + 7];
set<int> pos[2 * BASE + 7];

void upd(int ind, int val){
    ind += BASE;
    pos[ind].insert(val);
    tree[ind] = *pos[ind].begin();
    ind /= 2;
    while(ind > 0){
        tree[ind] = min(tree[2 * ind], tree[2 * ind + 1]);
        ind /= 2;
    }
}

void upd2(int ind, int val){
    ind += BASE;
    pos[ind].erase(val);
    tree[ind] = (sz(pos[ind]) > 0 ? *pos[ind].begin() : (int)1e9);
    ind /= 2;
    while(ind > 0){
        tree[ind] = min(tree[2 * ind], tree[2 * ind + 1]);
        ind /= 2;
    }
}

void upd3(int ind, int val){
    ind += BASE;
    while(ind > 0){
        tree2[ind] += val;
        ind /= 2;
    }
}

int query(int v, int l, int p, int a, int b){
    if(p < a || b < l){
        return 0;
    }

    if(a <= l && p <= b){
        return tree2[v];
    }
    int mid = (l + p) / 2;
    return query(2 * v, l, mid, a, b) + query(2 * v + 1, mid + 1, p, a, b);
}

ll count_swaps(vi s){
    for(int i = 0; i < 2 * BASE + 7; i++){
        tree[i] = 1e9;
    }

    int n = sz(s);
    for(int i = 0; i < n; i++){
        s[i] += n;
        upd(s[i], i);
    }

    ll ans = 0;
    for(int i = 0; i < n; i += 2){
        int akt = tree[1];
        if(s[akt] > n){
            ans++;
        }
        upd2(s[akt], akt);
        int d = *pos[BASE -(s[akt] - n) + n].begin();
        upd2(-(s[akt] - n) + n, d);

        ans =(ll)ans + (ll)abs(d - akt) - 1 - query(1, 0, BASE - 1, akt, d);
        upd3(akt, 1);
        upd3(d, 1);
    }

    return ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 15 / 15