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from collections import Counter
from itertools import chain, count
from sys import stdin
def safe(levels, dampened=False):
head = levels[0 if 0 < levels[1] - levels[0] < 4 else 1] - 1,
tail = levels[-1 if 0 < levels[-1] - levels[-2] < 4 else -2] + 1,
dampenable = tuple((not dampened and 0 < a - c < 4
and safe(levels[:i]+levels[i+1:], True))
for i, a, b, c in zip(count(),
chain(levels[1:], tail),
levels,
chain(head, levels))
if not (0 < a - b < 4 and 0 < b - c < 4))
return not dampenable or any(dampenable)
print(sum(safe(levels) or safe(tuple(map(int.__neg__, levels)))
for levels in (tuple(map(int, line))
for line in map(str.split, stdin))))
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