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Oct 11, 2018
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1 change: 1 addition & 0 deletions allalgorithms/searches/__init__.py
Original file line number Diff line number Diff line change
@@ -1,2 +1,3 @@
from .binary_search import *
from .fibonacci_search import *
from .jump_search import *
35 changes: 35 additions & 0 deletions allalgorithms/searches/fibonacci_search.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,35 @@
# -*- coding: UTF-8 -*-
#
# Fibonacci search works for a sorted array.
# The All ▲lgorithms library for python
#
# Contributed by: dieterpl
# Github: @dieterpl
#


def fibonacci_search(arr, query):
fib2, fib1 = 0, 1
fib = fib2 + fib1
hi = len(arr) - 1
while fib <= hi:
fib2 = fib1
fib1 = fib
fib = fib2 + fib1
offset = -1
while fib > 1:
i = min(offset + fib2, hi)
if arr[i] < query:
fib = fib1
fib1 = fib2
fib2 = fib - fib1
offset = i
elif arr[i] > query:
fib = fib2
fib1 = fib1 - fib2
fib2 = fib - fib1
else:
return i
if fib1 and arr[offset + 1] == query:
return offset + 1
return None
12 changes: 8 additions & 4 deletions changelog.md
Original file line number Diff line number Diff line change
Expand Up @@ -8,11 +8,12 @@ Date: October 9, 2018

### Algorithms:

- ### Sorting
- Bubble Sort
- ### Searches
- Merge Sort

- ### Sorting
- Bubble Sort

# Version `0.0.1`

Date: TO ADDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD, 2018
Expand All @@ -22,10 +23,13 @@ Date: TO ADDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD, 2018
Added:

- ### Searches
- Fibonacci Search
- Jump Search

- ### Sorting
- Bubble Sort
- Cocktail Shaker Sort
- Insertion Sort
- Pigeonhole Sort
- Selection Sort
- Stooge Sort
- Jump Search
- Stooge Sort
1 change: 1 addition & 0 deletions docs/readme.md
Original file line number Diff line number Diff line change
Expand Up @@ -59,6 +59,7 @@ print(binary_search(arr, 3))

- ### Searches
- [Binary Search](searches/binary-search)
- [Fibonacci Search](searches/fibonacci-search)
- [Jump Search](searches/jump-search)
- ### Sorting
- [Bubble Sort](sorting/bubble-sort)
Expand Down
33 changes: 33 additions & 0 deletions docs/searches/fibonacci-search.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,33 @@
# Fibonacci Search

In computer science, the Fibonacci search technique is a method of searching a sorted array using a divide and conquer algorithm that narrows down possible locations with the aid of Fibonacci numbers. (Wikipedia)
## Install

```
pip install allalgorithms
```

## Usage

```py
from allalgorithms.searches import fibonacci_search

arr = [-2, 1, 2, 7, 10, 77]

print(fibonacci_search(arr, 7))
# -> 3

print(fibonacci_search(arr, 3))
# -> None
```

## API

### fibonacci_search(array, query)

> Return array index if its found, otherwise returns `None`

##### Params:

- `array`: Sorted Array
- `query`: Element to search for in the array
2 changes: 2 additions & 0 deletions readme.md
Original file line number Diff line number Diff line change
Expand Up @@ -59,7 +59,9 @@ print(binary_search(arr, 3))

- ### Searches
- [Binary Search](https://python.allalgorithms.com/searches/binary-search)
- [Fibonacci Search](https://python.allalgorithms.com/searches/fibonacci-search)
- [Jump Search](https://python.allalgorithms.com/searches/jump-search)

- ### Sorting
- [Bubble Sort](https://python.allalgorithms.com/sorting/bubble-sort)
- [Cocktail Shaker Sort](https://python.allalgorithms.com/sorting/cocktail-shaker-sort)
Expand Down
15 changes: 12 additions & 3 deletions tests/test_searches.py
Original file line number Diff line number Diff line change
@@ -1,7 +1,10 @@
import unittest

from allalgorithms.searches import (binary_search, jump_search)

from allalgorithms.searches import (
binary_search,
fibonacci_search,
jump_search
)

class TestSearches(unittest.TestCase):

Expand All @@ -12,13 +15,19 @@ def test_binary_search(self):
self.assertEqual(None, binary_search(arr, 8))
self.assertEqual(None, binary_search(arr, -1))

def test_fibonacci_search(self):
arr = [1, 2, 3, 7, 10, 19, 27, 77]
self.assertEqual(3, fibonacci_search(arr, 7))
self.assertEqual(7, fibonacci_search(arr, 77))
self.assertEqual(None, fibonacci_search(arr, 8))
self.assertEqual(None, fibonacci_search(arr, -1))

def test_jump_search(self):
arr = [1, 2, 3, 7, 10, 19, 27, 77]
self.assertEqual(3, binary_search(arr, 7))
self.assertEqual(7, binary_search(arr, 77))
self.assertEqual(None, binary_search(arr, 8))
self.assertEqual(None, binary_search(arr, -1))


if __name__ == '__main__':
unittest.main()