# This program simulates flipping a coin 1000 times and then
# calculates the longest run of consecutive heads or consecutive 
# tails. Is this number larger or smaller than you would have
# guessed?

import random

def makestr(n):
    return [random.randint(0,1) for _ in xrange(n)]

def maxmonochrome(s):
    maxsofar = 0
    for i in range(len(s)):
        current = 0
        for j in range(len(s[i:])):
            if s[i] == s[i+j]:
                current = j+1
                if current > maxsofar:
                    maxsofar = current
            else:
                break
    return maxsofar

s = makestr(1000)
print maxmonochrome(s)