count fibonacci numbers as number of string over alphabet

Question

Hi Experts,

 

i am trying to make a program.

 

how to count string using Fibonacci numbers as numbers of strings over alphabets?

 

example: a=0,b=1 c=1,d=2,e=3,f=5,i=8..... like fibonacci series in alphabet order and end use put a string like : eidc
its sum count is 3+8+2+1=14


please help me.

Thanks & Regards
Ashish Sahu