Submission #44816

#	Time	Username	Problem	Language	Result	Execution time	Memory
44816		leehosu01	먼 별 (KOI16_dist)	C++17	2 / 100	122 ms	2304 KiB

dist

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
#define F(X) (X<0?-1:X>0)
ll T,MT,N,tms,bst=1ll<<62ll;
struct A{
int x,y,dx,dy;void SC(){cin>>x>>y>>dx>>dy;}
ll lcx(){return T*dx+x;}
ll lcy(){return T*dy+y;}
bool operator<(const A&X)const{return T*dx+x==T*X.dx+X.x?T*dy+y>T*X.dy+X.y:T*dx+x<T*X.dx+X.x;}
bool operator==(const A&X)const{return T*dx+x==T*X.dx+X.x&&T*dy+y==T*X.dy+X.y;}
ll Ds(A&X){return (lcx()-X.lcx())*(lcx()-X.lcx())+(lcy()-X.lcy())*(lcy()-X.lcy());}
}S[30001];
int cp(ll*X,ll*Y)
{
    ll T=0;
    for(int i=0;i<3;i++)
        T+=X[i]*Y[i+1]-X[i+1]*Y[i];
    return F(T);
}
int ccw(A&x0,A&x1,A&x2)
{
    A XA[4]={x0,x1,x2,x0};
    ll XX[4],YY[4];
    for(int i=0;i<4;i++)
    {
        XX[i]=XA[i].lcx();
        YY[i]=XA[i].lcy();
    }
    return cp(XX,YY);
}
inline ld slop(A&d1,A&d2)
{
    return ((ld)d1.lcy()-d2.lcy())/((ld)d1.lcx()-d2.lcx());
}
bool used[30001];
ll pro(int Ts)
{

    list<int>::iterator s1,s2;
    list<int>cov;
    T=Ts;
    sort(S,S+N);
    int K=1;
    memset(used,0,sizeof(used));
    for(int i=0;i>=0;i+=K)
    {
        if(i==N){K=-1,s1=cov.begin(),s2=--cov.end();continue;}
        if(i!=0&&used[i])continue;
        while(cov.size()>=2&&ccw(S[*(--(--cov.end()))],S[cov.back()],S[i])==-1){used[cov.back()]=0;cov.pop_back();}
        used[i]=1;cov.push_back(i);
    }//시작정점은 2번들어간다.

    ll MX=0;
    list<int>::iterator I=s1,It,J=s2,Jt;
    do{
        It=I;++It;
        Jt=J;++Jt;
        MX=max(MX,S[*I].Ds(S[*J]));
        MX=max(MX,S[*It].Ds(S[*J]));
        if(Jt!=cov.end())
        {
            MX=max(MX,S[*I].Ds(S[*Jt]));
            MX=max(MX,S[*It].Ds(S[*Jt]));
        }
        if(slop(S[*I],S[*It])<slop(S[*J],S[*Jt]))++I;
        else ++J;
    }while(It!=s2&&Jt!=cov.end());
    
    while(It!=s2){
        It=I;++It;
        MX=max(MX,S[*I].Ds(S[*J]));
        MX=max(MX,S[*It].Ds(S[*J]));
        if(Jt!=cov.end())
        {
            MX=max(MX,S[*I].Ds(S[*Jt]));
            MX=max(MX,S[*It].Ds(S[*Jt]));
        }
        ++I;
    }
    while(Jt!=cov.end()){
        Jt=J;++Jt;
        MX=max(MX,S[*I].Ds(S[*J]));
        MX=max(MX,S[*It].Ds(S[*J]));
        if(Jt!=cov.end())
        {
            MX=max(MX,S[*I].Ds(S[*Jt]));
            MX=max(MX,S[*It].Ds(S[*Jt]));
        }
        ++J;
    }
    if(MX<bst)bst=MX,tms=Ts;
    else if(MX==bst&&tms>Ts)tms=Ts;
    return MX;
}

int main()
{
    int i;

   //freopen("in.txt","r",stdin);
    cin>>N>>MT;
    for(i=0;i<N;i++)S[i].SC();
    ll l=0,r=MT,m,PS[3],minl,minI;
    while(l<r)
    {
        m=l+r>>1;
        minl=1ll<<62ll;
        minI=-1;
        for(i=-1;i<2;i++)
        {
            if(m+i>=0&&m+i<=MT)
            {
                PS[i+1]=pro(m+i);
                if(PS[i+1]<minl)
                {
                    minl=PS[i+1];
                    minI=i;
                }
            }
        }
        if(minI==-1)r=m-1;
        else if(minI==0)r=m;
        else l=m+1;
    }
    cout<<tms<<'\n'<<bst;

}

Compilation message (stderr)

dist.cpp: In function 'int main()':
dist.cpp:109:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
         m=l+r>>1;
           ~^~

• Subtask 1: 2 / 2
• Subtask 2: 0 / 40
• Subtask 3: 0 / 39
• Subtask 4: 0 / 19