#!/bin/bash

#
# Here is our main function. Like PHP, I could have simply placed this in the script
# rather than having a function. You notice that like C and PHP, the printf function
# still exists. Unlike C and PHP function calls do not enclose the parameters with 
# paraenthsis.

function main {
  printf "\nHow many numbers of the sequence would you like?\n"

  # Bash lets us use a function "read" to get input from stdin
  # Notice that we are not using a dollar sign in front of the variables when
  # we set them, but we need to when we use them.

  read n
  fibonacci $n

  # Again, I'm exiting with status 0

  exit 0
}

# Starting to look familiar? This function is actually a little different than the 
# C style for loop that we've used before. Instead we use while..do..done to accomplish
# the same thing. You'll also see that rather than specifying parameters in the 
# function;s declaration, we simply reference the variable "$1" to get the first parameter
# passed when the function was called.

function fibonacci {
  a=0
  b=1
  i=0

  while [ $i -lt $1 ]
  do
    printf "%d\n" $a
    let sum=$a+$b
    let a=$b
    let b=$sum
    let i=$i+1
  done
}

main