Submission #779580

#	Time	Username	Problem	Language	Result	Execution time	Memory
779580		Minindu206	Arranging Shoes (IOI19_shoes)	C++14	85 / 100	1038 ms	3104 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#define ll long long
using namespace std;
ll count_swaps(vector<int> s)
{
    ll n = s.size() / 2;
    if (n == 1)
        return s[0] > 0;
    int iseq = 1, fst = s[0], isame = 1;
    for (int i = 0; i < n; i++)
    {
        if (s[i] + s[i + n] != 0 || s[i] > 0)
            iseq = 0;
        if (s[i] != fst && s[i] != -fst)
            isame = 0;
    }
    if (iseq)
        return n * (n - 1) / 2;
    if (isame)
    {
        queue<int> ind;
        ll ans = 0LL;
        for (int i = 0; i < 2 * n; i++)
            if (s[i] < 0)
                ind.push(i);
        for (int i = 0; i < 2 * n; i += 2)
        {
            int cur = ind.front();
            ind.pop();
            ans += (abs(cur - i));
        }     
        return ans;
    }
    int cur = 0;
    ll ans = 0LL;
    while (cur < 2 * n)
    {
        int val = s[cur];
        if (val < 0)
        {
            int i = cur + 1;
            while (s[i] != -val)
                i++;
            s.erase(s.begin() + i);
            s.insert(s.begin() + cur + 1, -val);
            ans += (i - cur - 1);
        }
        else
        {
            int i = cur + 1;
            while (s[i] != -val)
                i++;
            s.erase(s.begin() + i);
            s.insert(s.begin() + cur, -val);
            ans += (i - cur);
        }
        cur += 2;
    }
    return ans;
}

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