import random


# divide and conquer to find max and min values in list
# shows how a pair of vals (x,y) can be returned
def find_max_min2(list, first, last):
    if first == last: # one item? it's both max and min
        maxval = minval = list[first]
    elif first < last:
        mid = (first+last)/2
        # next two lines assign 2-tuple returned to two variables
        (max_left,min_left) = find_max_min2(list, first, mid)
        (max_right,min_right) = find_max_min2(list, mid+1, last)
        maxval = max(max_left, max_right) # max() does 1 comparison
        minval = min(min_left, min_right) # min() does 1 comparison
    else:
        print "uh oh, didn't expect first > last: ", first, last
    return (maxval,minval)   # returns two values as a 2-tuple   

# creates a random list
def random_list(n, min=0, max=9):
    list = [] # empty list
    for i in range(n):
        list.append( random.randint(min, max) )
    return list


def main():
    # list = input('Enter the list: ')
    list = random_list(8, -9, 9)
    print list
    # variable pairs can be assigned values
    (maxval, minval) = find_max_min2(list, 0, len(list)-1)
    print maxval, minval
    return

    
main()