Submission #1092921

#	Time	Username	Problem	Language	Result	Execution time	Memory
1092921		TrinhKhanhDung	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	257 ms	407160 KiB

shoes

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define sz(x) (int)x.size()
#define ALL(v) v.begin(),v.end()
#define MASK(k) (1LL << (k))
#define BIT(x, i) (((x) >> (i)) & 1)
#define oo (ll)1e18
#define INF (ll)1e9
#define MOD (ll)(998244353)
#include "shoes.h"

using namespace std;

template<class T1, class T2>
    bool maximize(T1 &a, T2 b){if(a < b){a = b; return true;} return false;}

template<class T1, class T2>
    bool minimize(T1 &a, T2 b){if(a > b){a = b; return true;} return false;}

template<class T1, class T2>
    void add(T1 &a, T2 b){a += b; if(a >= MOD) a -= MOD;}

template<class T1, class T2>
    void sub(T1 &a, T2 b){a -= b; if(a < 0) a += MOD;}

template<class T>
    void cps(T &v){sort(ALL(v)); v.resize(unique(ALL(v)) - v.begin());}

struct fen{
    vector<int> tree;
    int n;

    fen(int _n = 0){
        n = _n;
        tree.resize(n + 3, 0);
    }

    void upd(int p, int c){
        while(p <= n){
            tree[p] += c;
            p += p & -p;
        }
    }

    int get(int p){
        int ans = 0;
        while(p > 0){
            ans += tree[p];
            p -= p & -p;
        }
        return ans;
    }

    int get(int l, int r){
        return get(r) - get(l - 1);
    }
};

ll count_swaps(vector<int> arr){
    int n = sz(arr);
    ll ans = 0;

    vector<vector<queue<int>>> ord(2, vector<queue<int>>(n + 1));
    for(int i = 0; i < n; i++){
        ord[arr[i] > 0][abs(arr[i])].push(i);
    }

    fen bit(n);
    for(int i = 1; i <= n; i++){
        bit.upd(i, 1);
    }

    vector<int> exist(n + 1, true);
    for(int i = 0; i < n; i++) if(exist[i]){
        if(arr[i] > 0) ans++;

        int t = ord[arr[i] < 0][abs(arr[i])].front();

        ord[arr[i] < 0][abs(arr[i])].pop();
        ord[arr[i] > 0][abs(arr[i])].pop();

        ans += bit.get((i + 1) + 1, (t + 1) - 1);
        bit.upd(t + 1, -1);
        exist[t] = false;
    }

    return ans;
}

//int main(){
//    ios_base::sync_with_stdio(0); cin.tie(0);
//
//    int t = count_swap({-2, 2, 2, -2, -2, 2});
//
//    cout << t << '\n';
//
//    return 0;
//}

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