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def sequenza(n, pollatz, tCollatz = -1):
tot = 1
if pollatz:
m = 5
else:
m = 3
pari = lambda n: ((n % 2) == 0)
while n != 1:
if pari(n):
n /= 2
else:
n = n*m+1
tot += 1
if tCollatz != -1 and tot > tCollatz:
break
return tot
with open('input.txt') as fin:
N = fin.readline().split(' ')
N[0] = int(N[0])
N[1] = int(N[1])
tot = 0
for i in range(N[0], N[1]+1):
collatz = sequenza(i, False)
if sequenza(i, True, collatz) < collatz:
tot += 1
with open('output.txt', 'w') as fout:
fout.write(str(tot))
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