Submission #1341590

#	Time	Username	Problem	Language	Result	Execution time	Memory
1341590		vjudge1	Arranging Shoes (IOI19_shoes)	C++20	0 / 100	1095 ms	348 KiB

shoes

#include <bits/stdc++.h>

using namespace std;

#define ll long long

const int M = 2e5 + 1;

int fen[M];

void modify(int p, int x)
{
	while (p<M)
		fen[p]+=x, p+=p&-p;
}

int get(int p)
{
	int ans=0;
	while (p)
		ans+=fen[p];
	return ans;
}

ll count_swaps(vector<int> v)
{
	int n=v.size(), ind[n+1];
	for (int i=0;i<n;i++)
		v[i]+=n, ind[v[i]]=i, modify(i+1,1);
	ll ans=0;
	for (int i=0;i<n;i++)
	{
		if (v[i]<=n)
		{
			if (ind[v[i]+n]<i) continue;
			ans+=get(ind[v[i]+n])-get(i+1);
		}
		else
		{
			if (ind[v[i]-n]<i) continue;
			ans+=get(ind[v[i]-n])-get(i+1)+1;
		}
	}
	return ans;
}

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