제출 #347863

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
347863		Kerim	Aliens (IOI16_aliens)	C++17	100 / 100	702 ms	8036 KiB

aliens

#include "aliens.h"
#include "bits/stdc++.h"
#define MAXN 100009
#define INF 1000000007
#define mp(x,y) make_pair(x,y)
#define all(v) v.begin(),v.end()
#define pb(x) push_back(x)
#define wr cerr<<"----------------"<<endl;
#define ppb() pop_back()
#define tr(ii,c) for(__typeof((c).begin()) ii=(c).begin();ii!=(c).end();ii++)
#define ff first
#define ss second
#define my_little_dodge 46
#define debug(x)  cerr<< #x <<" = "<< x<<endl;
using namespace std;

typedef long long ll;
typedef pair<ll,ll> PII;
template<class T>bool umin(T& a,T b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool umax(T& a,T b){if(a<b){a=b;return 1;}return 0;}
bool cmp(PII x,PII y){
	if(x.ff!=y.ff)
		return (x.ff<y.ff);
	return (x.ss>y.ss);	
}
ll sqr(int x){
	return x*1LL*x;	
}
const ll B=1e18;
ll dp[MAXN];
vector<ll>m,b;
vector<int>ind;
int sz,pos;
double inter(int l1,int l2){
	return double(b[l2]-b[l1])/double(m[l1]-m[l2]);	
}
bool bad(int l1,int l2,int l3){
	return inter(l1,l3)<inter(l1,l2);	
}
void upd(ll x,ll y,int z){
	m.pb(x);b.pb(y);ind.pb(z);sz++;
	while(sz>=3 and bad(sz-3,sz-2,sz-1))
		m.erase(m.end()-2),b.erase(b.end()-2),ind.erase(ind.end()-2),sz--;
}
pair<ll,int> get(ll x){
	assert(sz>0);
	umin(pos,sz-1);
	while(pos+1<sz and m[pos]*x+b[pos]>m[pos+1]*x+b[pos+1])pos++;
	return mp(m[pos]*x+b[pos],ind[pos]);		
}
vector<pair<int,int> >arr,v;
ll odp;
int cnt(int n,ll lambda){
	m.clear();b.clear();ind.clear();sz=pos=0;
	pair<ll,int> last=mp(0,0);
	for(int j=1;j<=n;j++){
		int h=j-1;
		if(last.ff!=B)
			upd(-(arr[h+1].ff-1),sqr(arr[h+1].ff-1)+last.ff-sqr(max(0,arr[h].ss-arr[h+1].ff+1)),last.ss);	
		last=get(2*arr[j].ss);
		if(last.ff!=B)
			last=mp(last.ff+lambda+sqr(arr[j].ss),last.ss+1);
	}odp=last.ff;
	return last.ss;	
}
ll take_photos(int n, int M, int k, vector<int> r, vector<int> c) {
	for(int i=0;i<n;i++)
		v.pb(mp(min(r[i],c[i]),max(r[i],c[i])));
	sort(all(v),cmp);arr.pb(mp(-1,-1));
	for(int i=0;i<int(v.size());i++)
		if(arr.back().ss<v[i].ss)
			arr.pb(v[i]);
	n=int(arr.size())-1;
	umin(k,n);
	//for(int i=1;i<=n;i++)
	//	printf("%d %d\n",arr[i].ff,arr[i].ss);
	ll st=0,en=ll(1e12);
	while(st+1<en){
		ll mid=(st+en)>>1;	
		debug(mid);
		debug(cnt(n,mid));
		if(cnt(n,mid)>=k)st=mid;
		else en=mid;
		debug(odp);
		debug(odp-mid*cnt(n,mid));
		wr
	}
	if(cnt(n,en)<=k)return odp-en*k;
	assert(cnt(n,st)<=k);
	return odp-st*k;
}

• Subtask 1: 4 / 4
• Subtask 2: 12 / 12
• Subtask 3: 9 / 9
• Subtask 4: 16 / 16
• Subtask 5: 19 / 19
• Subtask 6: 40 / 40