Submission #824452

#	Time	Username	Problem	Language	Result	Execution time	Memory
824452		caganyanmaz	Arranging Shoes (IOI19_shoes)	C++17	10 / 100	21 ms	3520 KiB

shoes

#include <bits/stdc++.h>
#define mp(x...) array<int, 2>({x})
#define pb push_back
#define int int64_t
#define vi vector<int32_t> 
using namespace std;
#include "shoes.h"

constexpr static int MXSIZE = 1e6 + 5;

struct Fenwick
{
	int v[MXSIZE];
	void set(int i, int val)	{ for (++i;i<MXSIZE;i+=i&(-i)) v[i] += val; }
	int get(int i) { int res = 0; for(++i;i;i-=i&(-i)) res += v[i]; return res; }
};

int subtask1(vi& s)
{
	if (s[0] > 0)
		return 1;
	else
		return 0;
}

Fenwick fw;
int last[MXSIZE];
map<array<int, 2>, int> pos;
int subtask4(vi& s)
{
	int n = s.size() / 2;
	for (int i = 0; i < n; i++)
	{
		array<int, 2> p = {-s[i], last[s[i]]++};
		pos[p] = i; // Leftover in the left
	}
	for (int i = 0; i < n; i++)
		last[i] = 0;
	int res = 0;
	for (int i = n; i < 2*n; i++)
	{
		assert(pos.find(mp(s[i], last[s[i]])) != pos.end());
		array<int, 2> p = {s[i], last[s[i]]++};
		int ps = pos[p];
		res += i-ps-1 - fw.get(ps);
		fw.set(ps, 1);
	}
	return res;
}

long long count_swaps(vi s)
{
	if (s.size() == 2)
		return subtask1(s);
	return subtask4(s);
	
}

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