Perguntas de entrevista de vagas de Software Development Engineer da empresa Fortinet

1-Multiplying two number without using * operator 2-finding pythagorean triples from a given array

First question was counting number of incorrect prices in an array. He then asked about improvements that could be made with data structures and threads. Second question was converting an int to string with and without using mod and division. Third question was counting the minimum amount of swaps needed such that an array contains all even numbers before odd numbers.