#include <stdio.h>
#include <math.h>

#define N 44995


int main( void )
{
  double a[N],b[N], c[N], d[N], e[N], dummy, disc, should, is;
  long int i, j;
  for(i=0; i<N; i++) {
    scanf("%lf", &a[i]);
    scanf("%lf", &b[i]);
    scanf("%lf", &c[i]);
    scanf("%lf", &d[i]);
    scanf("%lf", &e[i]);
    //    printf("%lf  %lf  %lf  %lf  %lf\n", a[i],b[i],c[i],d[i],e[i]);
  }
  disc=0;
  for(i=0; i<N; i++) {
    should=(1-exp(-a[i]))*(1-exp(-b[i]))*(1-exp(-c[i]))*(1-exp(-d[i]))*(1-exp(-e[i]));
    is=0;
    for(j=0; j<N; j++)
      if(a[j]<=a[i] && b[j]<=b[i] && c[j]<=c[i] && d[j]<=d[i] && e[j]<=e[i]) is++;
    is=is/N;
    if( fabs(should - is) > disc) disc = fabs(should-is);
  }
  printf("disc = %lf\n",disc);
  return 0;
}