fib (5) = fib(4) + fib(3)
fib(4) = fib(3) + fib(2)
fib(3) = fib(2) + fib(1)
fib(2) = fib(1) + fib(0)
Now, for last simplication, 1 additions. Then we store fib(2) in fibonacci array.
For fib(3), 1 addition. Again we store fib(3).
And so on. This is perfect example of dynamic programming.
So, answer = 4