You have a fraction a/b. You need to find the first occurrence of digit c into decimal notation of the fraction after decimal point.

The first contains three single positive integers a, b, c (1 <= a < b <= 10^5, 0 <= c <=9).

Print position of the first occurrence of digit c into the fraction. Positions are numbered from 1 after decimal point. It there is no such position, print -1.

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