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def f_1(s):

prev = s

while True:

s = s.replace('900', '8000', 1)

s = s.replace('70', '900', 1)

s = s.replace('8', '70', 1)

if len(s) == 71:

print(s)

return True

elif len(s) > 71:

print("No")

return False

elif prev == s:

return False

prev = s

print(f_1('1008'))

for i in range(1000, 10000):

if f_1(str(i)):

print(i)

break

print("finish")