// a8/p2 outline
//
#include <stdio.h>
#include <math.h>

#include "p2.h" // defines N and c[0]...c[N-1]

void slide( double y[], int n) {
//...
}

double filter( double c[], double y[], int n) {
//...
  return 0;
}

int main( void)
{
  double d, y[N] = {0};

  while( scanf( "%lf", &d) == 1) {
    slide(y,N);
    y[N-1] = d;
    printf( "%g\n", filter( c, y, N) );
  }

  return 0;
}