#include <stdio.h>
#include <stdlib.h>
float harmonicMean(int a[],int sizeOfarray,int index);
int main()
{
  int array[10] = {5,10,15,23,12,27,43-2};
  float HM = harmonicMean(array,10,0);
  printf("Harmonic mean is : %f\n",HM);
  return 0;
}
float harmonicMean(int a[],int sizeOfarray,int index)
{
  //printf("index = %d    val = %d \n",index,a[index]);
  if(index >= 10)
    return 0;
  if(a[index]<=0)
    return 0;
  float hm = harmonicMean(a,sizeOfarray,index+1);
  //printf("hm = %f\n",hm);
  if(hm == 0)
    return a[index];
  
  return ( hm * a[index] )/(hm + a[index]);
}