Created
May 4, 2020 11:00
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Given n, find k such that first n digits of 2^k == first n digits of 5^k == first n digits of sqrt(10)
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digits = "31622776601683795" | |
def find(n): | |
k = 0 | |
last_2 = 1 | |
last_5 = 1 | |
while True: | |
if first_n_digits(last_2, n) == digits[:n] \ | |
and first_n_digits(last_5, n) == digits[:n]: | |
return k | |
last_2 *= 2 | |
last_5 *= 5 | |
k+=1 | |
print(k) | |
def first_n_digits(n, n_digits): | |
n_string = f'{n}' | |
if len(n_string) < n_digits: | |
return n_string | |
return n_string[:n_digits] | |
def main(): | |
print(find(5)) | |
main() |
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