Submission #415597

#	Time	Username	Problem	Language	Result	Execution time	Memory
415597		CSQ31	Dancing Elephants (IOI11_elephants)	C++14	26 / 100	49 ms	2216 KiB

elephants

#include "elephants.h"
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define all(a) a.begin(),a.end()
#define sz(a) (int)(a.size())
#define ub upper_bound
typedef long long int ll;
typedef vector<vector<int>> vii;
typedef pair<int,int> pii;
int n,l;
vii bucket,reach,cnt;
vector<int>x,comp;
int blk = 500,num;
int find(int cur,int val){
	int l = 0,r = sz(bucket[cur])-1;
	while(r>=l){
		int mid = (l+r)/2;
		if(x[bucket[cur][mid]] <= val)l = mid+1;
		else r = mid-1;
	}
	return l;
}
void build1(vector<int>a,int cur){
	if(cur == sz(bucket)){
		bucket.pb(a);
		reach.pb(a);
		cnt.pb(a);
	}else bucket[cur] = reach[cur] = cnt[cur] = a;
	int last = bucket[cur].back();
	for(int i=sz(a)-1;i>=0;i--){
		int v = bucket[cur][i];
		comp[v] = cur;
		if(x[v]+l >= x[last]){
			reach[cur][i] = x[v]+l;
			cnt[cur][i] = 1;
		}else{
			int p = find(cur,x[v]+l);
			reach[cur][i] = reach[cur][p];
			cnt[cur][i] = cnt[cur][p]+1;
			
		}
	}
}
void build2(){
	bucket.clear();
	cnt.clear();
	reach.clear();
	vector<pii>a;
	for(int i=0;i<n;i++)a.pb({x[i],i});
	sort(all(a));
	for(int i=0,j=0;i<n;i+=blk,j++){
		vector<int>b;
		for(int k=i;k<min(n,i+blk);k++)b.pb(a[k].second);
		build1(b,j);
	}
}
void init(int N, int L, int X[])
{
  n = N;
  l = L;
  x.resize(n);
  comp.resize(n);
  for(int i=0;i<n;i++)x[i] = X[i];
  build2();
}
 
int update(int i, int y)
{
	if(num == blk-1)build2();
	else{
		num%=blk;
		int c = comp[i];
		vector<int>a;
		for(int x:bucket[c]){
			if(x != i)a.pb(x);
		}
		build1(a,c);
		x[i] = y;
		for(int i=0;i<sz(bucket);i++){
			if(y <= x[bucket[i].back()]){
				c = i;
				break;
			}
		}
		if(y > x[bucket.back().back()])c = sz(bucket)-1;
		a = bucket[c];
		a.pb(i);
		sort(all(a),[&](const int &i,const int &j){return x[i] < x[j];});
		build1(a,c); 
	}
		int ans = cnt[0][0];
		int cur = reach[0][0];
		for(int i=1;i<sz(bucket);i++){
			if(cur >= x[bucket[i].back()])continue;
			int idx = find(i,cur);
			cur = reach[i][idx];
			ans+=cnt[i][idx];
		}
  //for(int i=0;i<n;i++)cout<<x[bucket[0][i]]<<" "<<reach[0][i]<<" "<<cnt[0][i]<<'\n';
   num++;
   return ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 16 / 16
• Subtask 3: 0 / 24
• Subtask 4: 0 / 47
• Subtask 5: 0 / 3