list_scanner_advanced.py

import random, time


def split_list(alist, wanted_parts=1): ##splits a list into equle chunks
    length = len(alist)
    return [ alist[i*length // wanted_parts: (i+1)*length // wanted_parts] for i in range(wanted_parts)]

def tester(chunk, i):
    mid = len(chunk)/2
    if i == 0:
        thisnum = chunk[mid]
        if not chunk[mid-1] == chunk[mid]-1 or not chunk[mid+1] == chunk[mid]+1:
            return True, thisnum+1
    else:
        thisnum = chunk[mid-i]
        if not chunk[mid-i-1] == chunk[mid-i]-1 or not chunk[mid-i+1] == chunk[mid-i]+1:
            return True, thisnum-1
        thisnum = chunk[mid+i]
        if not chunk[mid+i-1] == chunk[mid+i]-1 or not chunk[mid+i+1] == chunk[mid+i]+1:
            return True, thisnum+1
    return False, 0

def scan(chunks):
    found_list = []
    chunk_found = len(chunks)
    mid = len(chunks[0])/2
    for i in range(mid):
        for x in range(len(chunks)):
            if chunk_found > x+1:
                found, num = tester(chunks[x], i)
                if found:
                    found_list.append(num)
                    chunk_found = x+1
    return min(found_list)

def main():
    x = range(10000)
    for i in range(5):
        rem = random.randint(0, 9999)
        if rem in x:
            print("removing %s" %rem)
            x.remove(rem)
        else:
            i+=1
    chks = split_list(x, 10)
    return scan(chks)

if __name__ == "__main__":
    times = []
    for i in range(1000):
        start = time.time()
        lowest_missing = main()
        end = time.time() - start
        times.append(end)
        print("Found the lowest missing value as %s in %ss" %(lowest_missing,end))
    avarage = reduce(lambda x, y: x + y, times) / float(len(times))
    print("avarage time: %s" %avarage)