Submission #1173980

#	Time	Username	Problem	Language	Result	Execution time	Memory
1173980		somefolk	Arranging Shoes (IOI19_shoes)	C++20	0 / 100	0 ms	324 KiB

shoes

#include <iostream>
#include <cmath>
#include <algorithm>
#include <string>
#include <vector>
#include <map>
#include <unordered_map>
#include <queue>
#include <set>
#include <unordered_set>
#include <complex>
#include <list>
#include <cassert>
#include <chrono>
#include <random>
#include <stack>
#include <iomanip>
#include <fstream>
using namespace std;

#define endl "\n"
#define int long long

const int INF = 1e5+7;
const int MOD = 1e9+7;

int top(unordered_map<int, int> &dist){
    int mn1 = -1, mn2 = INF;
    for(auto &i : dist){
        if(i.second < mn2){
            mn1 = i.first;
            mn2 = i.second;
        }
    }
    return mn1;
}

int64_t count_swaps(vector<int32_t> a){
    int n = a.size();

    if(n == 1){
        if(a[1] < a[0]) return 1;
        else return 0;
    } else if(n <= 8){
        unordered_map<int, set<int>> mid;
        unordered_map<int, int> used;
        for(int i = 0; i < n; i++){
            if(!used[abs(a[i])]){
                used[abs(a[i])] = true;
                for(int j = i+1; j < n; j++){
                    if(abs(a[j]) == abs(a[i])) break;
                    mid[abs(a[i])].insert(abs(a[j]));
                }
            }
        }

        unordered_map<int, int> dist;
        for(int i = 0; i < n; i++){
            if(used[abs(a[i])]){
                used[abs(a[i])] = false;
                if(a[i] > 0) dist[abs(a[i])]++;
                dist[abs(a[i])] += i;
            } else {
                dist[abs(a[i])] = abs(dist[abs(a[i])] - i);
            }
        }

        int sol = 0, mn = top(dist);
        while(dist[mn] != INF){
            sol += dist[mn];
            dist[mn] = INF;
            for(auto &i : mid[mn]){
                if(dist[i] != INF) dist[i]--;
            }
            mn = top(dist);
        }

        return sol;
    } else {
        vector<int> pos, neg;
        for(int i = 0; i < n; i++){
            if(a[i] > 0 && i%2==0) pos.push_back(i);
            else if(a[i] < 0 && i%2!=0) neg.push_back(i);
        }

        int sol = 0, idx = 0;
        if(pos.size() < neg.size()){
            for(auto &i : pos){
                sol += abs(i-neg[idx]);
                idx++;
            }
        } else {
            for(auto &i : neg){
                sol += abs(i-pos[idx]);
                idx++;
            }
        }
        return sol;
    }
}

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