binary search

def binarySearch(alist, item):
    first = 0
    last = len(alist)-1
    found = False

    while first <= last and not found:
        midpoint = (first + last) // 2
        if alist[midpoint] == item:
            found = True
        else:
            if item < alist[midpoint]:
                last = midpoint-1
            else:
                first = midpoint+1
        return found

recursion

function recursive(input):
    if input <= 0
        return input
    else
        output = recursive(input - 1)
        return output

fib

function getFib(position){
    if (position == 0) { return 0; }
    if (position == 1) { return 1; }
    var first = 0,
        second = 1,
        next = first + second;
    for (var i = 2; i < position; i++){
        first = second;
        second = next;
        next = first + second;
    }
    return next;
}

def get_fib(position):
    if position == 0 or position == 1:
        return position
    return get_fib(position -1) + get_fib(position -2)

margin sort efficiency
log(n)
1, 4(log n1),8(log n3), 16(log n4)

ease yourself by commic
https://xkcd.com/1185/

margin sort text
http://algs4.cs.princeton.edu/22mergesort/

quick sort

def quicksort(array):
    if len(array) < 1:
        return array
    pivot = array[0]
    left = []
    right = []
    for x in range(1, len(array)):
        if array[x] <= pivot:
            left.append(array[x])
        else:
            right.append(array[x])
        left = quicksort(left)
        right = quicksort(right)
        foo = [pivot]
        return left + foo + right

list: A B C
set: C A B