1
0
Fork 0
mirror of https://github.com/jashkenas/coffeescript.git synced 2022-11-09 12:23:24 -05:00
jashkenas--coffeescript/examples/beautiful_code/binary_search.coffee
2010-01-29 23:30:54 -05:00

16 lines
No EOL
499 B
CoffeeScript

# Beautiful Code, Chapter 6.
# The implementation of binary search that is tested.
# Return the index of an element in a sorted list. (or -1, if not present)
index: (list, target) ->
[low, high]: [0, list.length]
while low < high
mid: (low + high) >> 1
val: list[mid]
return mid if val is target
if val < target then low: mid + 1 else high: mid
return -1
puts 2 is index([10, 20, 30, 40, 50], 30)
puts 4 is index([-97, 35, 67, 88, 1200], 1200)
puts 0 is index([0, 45, 70], 0)