Submission #797957

#	Time	Username	Problem	Language	Result	Execution time	Memory
797957		Mularstyle	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	121 ms	141392 KiB

shoes

#include<bits/stdc++.h>
using namespace std;

#include "shoes.h"
#define ll long long
int n;
ll ar[200005];
bool vis[200005];
void up(int idx,int x)
{
    while(idx<=n)ar[idx]+=x,idx+=(idx&-idx);
}

int re(int idx)
{
    ll sum=0;
    while(idx>0)sum+=ar[idx],idx-=(idx&-idx);
    return sum;
}

long long count_swaps(std::vector<int> os) {

    ll ans=0;
    n=os.size();
    int s[n+5];

    for(int i=1;i<=n;i++)
        s[i]=os[i-1];

    queue<int> S[n];
    int pidx[n+5];

    for(int i=1;i<=n;i++)
    {
        up(i,1);
        if(S[abs(s[i])].empty())
            S[abs(s[i])].push(i);
        else
        {
            int tmp=S[abs(s[i])].front();
            if(s[i]!=s[tmp])//pair
            {
                pidx[i]=tmp;
                pidx[tmp]=i;
                S[abs(s[i])].pop();
            }
            else
            {
                S[abs(s[i])].push(i);
            }
        }
    }


    for(int i=1;i<=n;i++)
    {

    if(vis[pidx[i]])continue;
     vis[i]=1;

      // ans+=re(pidx[i]);
        ans+=( ( re(pidx[i])-re(i-1) )  -2  );

       if(s[i]>0)//rightonleft
           ans++;

        up(i,-1);
        up(pidx[i],-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