Strings

import random
a = 0
b = 1
n=  10
T = 100000
k = 0
L = 0

for u in range(0, T):
     R = [random.randint(0,1) for r in xrange(n)]
     k = 0
     L = L + 1
     for i in range(0,n-1):
        if R[i] == R[i+1]:
            k = k + 1
        else:
            k = 0
        if k == 2:
             L = L - 1
             break

print(100*L/T)