Submission #1011055

#	Time	Username	Problem	Language	Result	Execution time	Memory
1011055		rythm_of_knight	Arranging Shoes (IOI19_shoes)	C++14	0 / 100	0 ms	604 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#define ll long long
using namespace std;
 
struct Fenwick{
    vector<int> tr;
    int sz;
    Fenwick(int N){
        tr.resize(N+1);
        sz=N;
    }
    void add(ll i, ll x){
        for (; i<=sz; i+=(-i&i)) tr[i]+=x;
    }
    ll get(ll i){
        ll sum=0;
        for (; i; i-=(i&-i)) sum+=tr[i];
        return sum;
    }
};
long long count_swaps(vector<int> s) {
	int n = s.size(), x;
	ll ans = 0, res = 0;
    vector <int> v = s;
    // cin >> n;
//    sgt st;
//    st.init(n);
    Fenwick tr(n+2);
    vector <deque <int>> p(n + 1, deque <int>()), m(n + 1, deque <int>());
    for (int i = 0; i < n; i++) {
        // cin >> x;
        x = v[i];
        if (x > 0) {
            if (!m[x].empty()) {
                int it = m[x].front(); m[x].pop_front();
                int l = it + tr.get(it+1), r = i;
                int j = i;
                while (abs(s[j]) != abs(s[j - 1]) || s[j - 1] > s[j])
                    swap(s[j], s[j - 1]), j--, res++;
                ans += r - l - 1;
                tr.add(l+1, 1);
                tr.add(r+2, -1);
            } else {
                p[x].push_back(i);
            }
        } else {
            x = -x;
            if (!p[x].empty()) {
                int j = i;
                while (abs(s[j]) != abs(s[j - 1]) || s[j - 1] > s[j])
                    swap(s[j], s[j - 1]), j--, res++;
                int it = p[x].front(); p[x].pop_front();
                int l = it + tr.get(it+1), r = i;
                ans += r - l;
                tr.add(l+1, 1);
                tr.add(r+2, -1);
            } else {
                m[x].push_back(i);
            }
        }
    }
    // if (ans != res) {
    //     cout << ans << ' ' << res << '\n';
    //     for (int &i : v)
    //         cout << i << ' ';
    //     cout << '\n';
    // }
	return res;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 15