Submission #520883

#	Time	Username	Problem	Language	Result	Execution time	Memory
520883		JvThunder	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	237 ms	274372 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
queue<int> s1[2][200005];
ll ft[200005] = {0};

void upd(ll i,ll val)
{
	for(;i<=200000;i+=i&-i) ft[i] += val;
}

ll query(int j)
{
	ll ans = 0;
	for(;j;j-=j&-j) ans += ft[j];
	return ans;
}

ll count_swaps(vector<int> s) 
{
	for(int i=1;i<=200000;i++) upd(i,1);
	
	ll ans = 0;
	for(int i=0;i<s.size();i++)
	{
		ll type = 1;
		if(s[i]<0) type = 0;
		ll tmp = abs(s[i]);
		if(!s1[type][tmp].empty())
		{
			ll x = s1[type][tmp].front();
			ll tans = query(i) - query(x);
			upd(i+1,-1);
			upd(x,1); 
			s1[type][tmp].pop();
			if(type==0) tans++;
			ans += tans;		
		}
		else s1[1-type][tmp].push(i+1);
	}
	return ans;
}

Compilation message (stderr)

shoes.cpp: In function 'll count_swaps(std::vector<int>)':
shoes.cpp:25:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |  for(int i=0;i<s.size();i++)
      |              ~^~~~~~~~~

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