Algebra Problem by Sir

You are in your algebra class and today you are dealing with numbers. You are given two positive integers x, y by your mathematics sir, and are supposed to find the smallest positive integer z such that z contains x as a prefix (in base 10) and z is divisible by y. If the smallest such z>10¹⁸, print -1. ### Input - The first line of the input contains an integer T denoting the number of test cas