Onsite Interview: Interview 1: Intersection of two array with or without space? factorial of number with or without recurssion Cube color problem(Given a bigger cube with 10*10*10 which consist of unit cubes. All six surfaces of cubes are painted, how many cubes left which don't have any color on them) Interview 2: "Given a list of sorted words, output the order of the letters used to sort them." And finally sort the another set of words with resulted order. How can i generate a unique int from a unique string. Give your Algorithm to make a hashmap <key: string, value:int> . Example, Alex and Leax should give different integer values. It should be for unique for every word. I know this is not possible as there are infinite words of characters, so give a hashfunction which give us rare collision