Cod sursa(job #1738364)

Utilizator ionanghelinaIonut Anghelina ionanghelina Data 6 august 2016 16:21:18
Problema Secventa 3 Scor 60
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.32 kb
#include<bits/stdc++.h>
#define INF 30000000
#define maxN 30005
using namespace std;
deque<int> q;
double s[maxN],m[maxN];
int n,a[maxN],b[maxN],u,l;
double val(double r)
{
    s[0]=0;
    for(int i=1;i<=n;i++)
    {
        s[i]=s[i-1]+100*a[i]-r*b[i];
    }
    while (!q.empty()) q.pop_front();
    int d=u-l+1;
    for(int i=1;i<=n;i++)
    {
        while (!q.empty() && s[q.back()]>=s[i])
        {
            q.pop_back();
        }
        q.push_back(i);
        while (q.front()<=(i-d)) q.pop_front();
        if (i>=d)
        {
            m[i]=s[q.front()];
        }
    }
    double maxim=-INT_MAX;
    for(int i=l;i<=u;i++)
    {
        if (s[i]>maxim) maxim=s[i];
    }
    for(int i=(u+1);i<=n;i++)
    {
        if ((s[i]-m[i-l])>maxim) maxim=s[i]-m[i-l];
    }
   if (maxim>=0) return 1;
   return 0;
}
int main()
{
    freopen("secv3.in","r",stdin);
    freopen("secv3.out","w",stdout);
    scanf("%d%d%d",&n,&l,&u);
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&a[i]);
    }
    for(int i=1;i<=n;i++)
    {
        scanf("%d",&b[i]);
    }
    double ls=0;
    double ld=INF;
    double mid;
    while (ls<=ld)
    {
        mid=(ls+ld)/(2);
        if(val(mid)) ls=mid+1;
            else ld=mid-1;
    }
    printf("%.2lf\n",((ld-1)/100.0));
    return 0;
}