Submission #294937

#	Time	Username	Problem	Language	Result	Execution time	Memory
294937		Fasho	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	493 ms	419368 KiB

shoes

#include <bits/stdc++.h>
#define N 200005
#define ll long long int
#define fo(i,x,y)	for(int i=x;i<=y;i++)
#define fs(ar,n) fo(i,1,n) cin>>ar[i]
#define sp " "
#define fast cin.tie(0);cout.tie(0);ios_base::sync_with_stdio(false)
#define pb push_back
#define ppb pop_back
#define fi first
#define se second
#define ii pair<int,int>
#define lli pair<ll,ll> 
#include "shoes.h"
using namespace std;
 
ll n,m,ar[N],sum,tree[4*N],lazy[4*N],mark[N],tutmac[N][3],tut[N];
 
stack<int> st[N][3];
 
void build(int ind,int l,int r)
{
	if(l==r)
	{
		tree[ind]=l;
		return;
	}
	int mid=(l+r)/2;
	build(ind*2,l,mid);
	build(ind*2+1,mid+1,r);
}
 
void push(int ind,int l,int r)
{
	ll x=lazy[ind];
	lazy[ind]=0;
	tree[ind]+=x;
	if(l==r)
		return;
	lazy[ind*2]+=x;
	lazy[ind*2+1]+=x;
}
 
ll query(int ind,int l,int r,int a)
{
	if(l>a || r<a)
		return 0;
	push(ind,l,r);
	if(l==r)
		return tree[ind];
	int mid=(l+r)/2;
	if(a<=mid)
		return query(ind*2,l,mid,a);
	else
		return query(ind*2+1,mid+1,r,a);
}
void upd(int ind,int l,int r,int a,int b)
{
	if(l>b || r<a)
		return;
	push(ind,l,r);
	if(l>=a && r<=b)
	{
		lazy[ind]++;
		push(ind,l,r);
		return;
	}
	int mid=(l+r)/2;
	upd(ind*2,l,mid,a,b);
	upd(ind*2+1,mid+1,r,a,b);
}
 
void pre()
{
	for(int i=n;i>=1;i--)
	{
		if(ar[i]<0)
			st[-ar[i]][0].push(i);
		else
			st[ar[i]][1].push(i);
	}
 
}
 
long long count_swaps(std::vector<int> s) {
	n=s.size();
	fo(i,1,n)
		ar[i]=s[i-1];
	pre();
	build(1,1,n);
	
 
	// cout<<query(1,1,n,7)<<endl;
	// upd(1,1,n,1,6);
	// upd(1,1,n,2,4);
	// cout<<query(1,1,n,7)<<endl;
	// cout<<endl;	
 
	fo(i,1,n)
	{
		if(mark[i])
			continue;
		mark[i]=1;
 
		if(ar[i]>0)
		{
			while(mark[st[ar[i]][0].top()])
				st[ar[i]][0].pop();
			ll x=st[ar[i]][0].top();
			mark[x]=1;
			ll a=query(1,1,n,i);
			ll b=query(1,1,n,x);
			sum+=b-a;
			// cerr<<i<<sp<<x<<sp<<a<<sp<<b<<endl;
			upd(1,1,n,i,x-1);
		}
		else
		{
			while(mark[st[-ar[i]][1].top()])
				st[-ar[i]][1].pop();
			ll x=st[-ar[i]][1].top();
			mark[x]=1;
			ll a=query(1,1,n,i);
			ll b=query(1,1,n,x);
			sum+=b-a-1;
			// cerr<<i<<sp<<x<<sp<<a<<sp<<b<<endl;
			upd(1,1,n,i,x-1);
 
		}
		
	}
 
	return sum;
}
// int main() {
// 	int n;
// 	assert(1 == scanf("%d", &n));
// 	vector<int> S(2 * n);
// 	for (int i = 0; i < 2 * n; i++)
// 		assert(1 == scanf("%d", &S[i]));
// 	fclose(stdin);
 
// 	long long result = count_swaps(S);
 
// 	printf("%lld\n", result);
// 	fclose(stdout);
// 	return 0;
// }

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