Submission #872221

#	Time	Username	Problem	Language	Result	Execution time	Memory
872221		imarn	Balloons (CEOI11_bal)	C++14	100 / 100	175 ms	4948 KiB

bal

#include<bits/stdc++.h>
#define f first
#define s second
#define ll long long
#define pb push_back
#define pii pair<int,int>
#define pll pair<ll,ll>
#define sz(x) (int)x.size()
#define all(x) x.begin(),x.end()
using namespace std;
#include<bits/stdc++.h>
#define pb push_back
#define f first
#define ll long double
#define s second
#define vll vector<ll>
#define vi vector<int>
#define sz(x) (int)x.size()
using namespace std;
ll inf=1e18;
bool qr;
struct line{
	mutable ll m,c,p;
	line(ll p):m(0),c(inf),p(p){}
	line(ll m,ll c):m(m),c(c),p(0){}
	bool operator<(const line &o)const{return qr?p<o.p:m>o.m;}
};
struct convexhull:multiset<line>{
	bool isect(iterator x,iterator y){
		if(y==end())return x->p=inf,0;
		if(x->m==y->m)x->p=x->c<=y->c?inf:-inf;
		else x->p=(x->c-y->c)/(y->m-x->m);
		return x->p>=y->p;
	}
	void add(ll m,ll c){
		auto y=insert(line(m,c)),x=y,z=next(y);
		while(isect(y,z))z=erase(z);
		if(x!=begin()&&isect(--x,y))isect(x,erase(y));
		while((y=x)!=begin()&&(--x)->p>=y->p)isect(x,erase(y));
	}
	ll get(ll x){
		if(empty())return inf;
		qr=1;auto l=lower_bound(line(x));qr=0;
		return l->m*x+l->c;
	}
}cht;
int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    int n;cin>>n;
    ll a[n];
    ll x,r;cin>>x>>r;a[0]=r;
    cht.add(1.0/(2.0*sqrt(r)),-x/(2.0*sqrt(r)));
    for(int i=1;i<n;i++){
        cin>>x>>r;ll y = cht.get(x);
        r = min(r,y*y);a[i]=r;
        cht.add(1.0/(2.0*sqrt(r)),-x/(2.0*sqrt(r)));
    }
    for(int i=0;i<n;i++)cout<<fixed<<setprecision(3)<<a[i]<<"\n";
}

Compilation message (stderr)

bal.cpp:14: warning: "ll" redefined
   14 | #define ll long double
      | 
bal.cpp:4: note: this is the location of the previous definition
    4 | #define ll long long
      |

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10