Submission #213078

#	Time	Username	Problem	Language	Result	Execution time	Memory
213078		iris2617	Arranging Shoes (IOI19_shoes)	C++14	Compilation error	0 ms	0 KiB

shoes

#include "shoes.h"
#include <queue>
#define int long long
using namespace std;

int arr[200010],n;
queue<int> q[200010],q2[200010];
int bit[200010];
bool used[200010];

void build()
{
	int i;
	for(i=1;i<=n;i++)
	{
		if(i+(i&(-i))<=n)
		{
			bit[i+(i&(-i))]+=bit[i];
		}
	}
}

void add(int a,int k)
{
	int i;
	for(i=a;i<=n;i+=(i&(-i)))
	{
		bit[i]+=k;
	}
}

int sum(int a)
{
	int i,res=0;
	for(i=a;i;i-=(i&(-i)))
	{
		res+=bit[i];
	}
	return res;
}

long long count_swaps(std::vector<int> s)
{
	int i,ans,a;
	ans=0;
	
	n=s.size();
	for(i=1;i<=n;i++)
	{
		a=s[i-1];
		if(a<0)
		{
			q[-a].push(i);
		}
		else
		{
			q2[a].push(i);
		}
		arr[i]=a;
		bit[i]=1;
	}
	build();
	for(i=1;i<=n;i++)
	{
		if(used[i])
		{
			continue;
		}
		used[i]=1;
		
		if(arr[i]>0)
		{
			add(q[arr[i]].front(),-1);
			add(i,-1);
			ans+=sum(q[arr[i]].front())+1;
			used[q[arr[i]].front()]=1;
		}
		else
		{
			arr[i]*=-1;
			add(q2[arr[i]].front(),-1);
			add(i,-1);
			ans+=sum(q2[arr[i]].front());
			used[q2[arr[i]].front()]=1;
		}
		q[arr[i]].pop();
		q2[arr[i]].pop();
	}
	return ans;
}

Compilation message (stderr)

/tmp/ccDcccK9.o: In function `main':
grader.cpp:(.text.startup+0x272): undefined reference to `count_swaps(std::vector<int, std::allocator<int> >)'
collect2: error: ld returned 1 exit status