Miroirs/TheAlgorithms-Ruby
1
0
Fork 0
mirror of https://github.com/TheAlgorithms/Ruby synced 2024-11-16 19:50:00 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

Minor changes

Browse source
This commit is contained in:
Vitor Oliveira 2021-03-07 12:54:10 -08:00
parent 2d2d1414d6
commit 4ef0224ede
1 changed files with 8 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
dynamic_programming/fast_fibonacci.rb → dynamic_programming/fibonacci.rb
View file

@ -1,9 +1,10 @@
# The Fibonacci numbers, commonly denoted F(n) form a sequence,
# called the Fibonacci sequence, such that # each number is the sum
# of the two preceding ones, starting from 0 and 1. That is,
#
# F(0) = 0, F(1) = 1
# F(n) = F(n - 1) + F(n - 2), for n > 1.
# F(n) = F(n - 1) + F(n - 2), for n > 1
#
# Given n, calculate F(n).
#
@ -15,10 +16,11 @@
# Time complexity: O(n). Each number, starting at 2 up to and
# including N, is visited, computed and then stored for O(1) access
# later on.
#
# Space complexity: O(n). The size of the stack in memory is
# proportionate to N.
#
def fib(n)
def fibonacci(n)
return n if n <= 1
cache = {}
@ -37,16 +39,16 @@ def memoize(n, cache)
end
n = 2
fibonacci(n)
# Output: 1
# Explanation: F(2) = F(1) + F(0) = 1 + 0 = 1.
puts(fib(n))
n = 3
fibonacci(n)
# Output: 2
# Explanation: F(3) = F(2) + F(1) = 1 + 1 = 2.
puts(fib(n))
n = 4
fibonacci(n)
# Output: 3
# Explanation: F(4) = F(3) + F(2) = 2 + 1 = 3.
puts(fib(n))