Submission #225004

#	Time	Username	Problem	Language	Result	Execution time	Memory
225004		alishahali1382	ČVENK (COI15_cvenk)	C++14	100 / 100	2520 ms	3064 KiB

cvenk

#include <bits/stdc++.h>
#pragma GCC optimize ("O2")
#pragma GCC optimize ("unroll-loops")
//#pragma GCC optimize("no-stack-protector,fast-math")

using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<pii, int> piii;
typedef pair<ll, ll> pll;
#define debug(x) cerr<<#x<<'='<<(x)<<endl;
#define debugp(x) cerr<<#x<<"= {"<<(x.first)<<", "<<(x.second)<<"}"<<endl;
#define debug2(x, y) cerr<<"{"<<#x<<", "<<#y<<"} = {"<<(x)<<", "<<(y)<<"}"<<endl;
#define debugv(v) {cerr<<#v<<" : ";for (auto x:v) cerr<<x<<' ';cerr<<endl;}
#define all(x) x.begin(), x.end()
#define pb push_back
#define kill(x) return cout<<x<<'\n', 0;

const ld eps=1e-7;
const int inf=1000000010;
const ll INF=10000000000000010LL;
const int mod=1000000007;
const int MAXN=100010, LOG=20;

ll n, m, k, u, v, x, y, t, a, b, ans=INF;
pii A[MAXN];
int P[MAXN];
map<pair<pii, pii>, pii> mp;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

inline pii GetPar(pii p, int k){
	int x=p.first, y=p.second;
	while (k){
		int xx=(x&-x), yy=(y&-y);
		if (!xx) xx=2*inf;
		if (!yy) yy=2*inf;
		int tmp=min(k, min(xx, yy));
		k-=tmp;
		if (xx<yy) x-=tmp;
		else y-=tmp;
	}
	return {x, y};
}

inline ll GetH(pii p){
	return p.first+p.second;
}

inline pii Lca(pii x, pii y){
	if (GetH(x)<GetH(y)) swap(x, y);
	x=GetPar(x, GetH(x)-GetH(y));
	if (x==y) return x; // :)
	
	if (x<y) swap(x, y);
	if (mp.count({x, y})) return mp[{x, y}];
	
	int dwn=0, up=GetH(x);
	while (up-dwn>1){
		int mid=(dwn+up)>>1;
		if (GetPar(x, mid)==GetPar(y, mid)) up=mid;
		else dwn=mid;
	}
	return mp[{x, y}]=GetPar(x, up);
}

inline ll Dist(pii x, pii y){
	return GetH(x)+GetH(y)-2*GetH(Lca(x, y));
}

inline int GetSz(pii p){    // O(n.lg)
	int res=0;
	for (int i=1; i<=n; i++)
		if (GetH(p)<=GetH(A[i]))
			res+=(GetPar(A[i], GetH(A[i])-GetH(p))==p);
	return res;
}

inline void check(pii v){  // O(n.lg^2)
	ll sum=0;
	for (int i=1; i<=n; i++){
		sum+=Dist(A[i], v);
		if (sum>=ans) return ; //  :)
	}
	ans=min(ans, sum);
}

inline void check2(pii v){ // O(n.lg^2)
	int dwn=-1, up=GetH(v);
	while (up-dwn>1){
		int mid=(dwn+up)>>1;
		if (GetSz(GetPar(v, mid))*2>n) up=mid;
		else dwn=mid; 
	}
	check(GetPar(v, up));
}

int main(){
	ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	//freopen("input.txt", "r", stdin);
	//freopen("output.txt", "w", stdout);
	cin>>n;
	for (int i=1; i<=n; i++) cin>>A[i].first>>A[i].second, P[i]=i;
	shuffle(P+1, P+n+1, rng);
	
	for (int i=1; i<=min(n, 6ll); i++) check2(A[P[i]]);
	cout<<ans<<'\n';
	
	return 0;
}

• Subtask 1: 17 / 17
• Subtask 2: 21 / 21
• Subtask 3: 22 / 22
• Subtask 4: 40 / 40