Philips Software Developer I interview questions

The question from 2 technical interviews: 1)Provide a design of the searching for a word in the file system,i.e. given a word return all files where the word appears. 2)Provide a design of the puzzle solver 3)Given an unsorted array of integers and integer x, find all pairs of integers from the array which sum is x. 4)Reverse linked list 5)Represent a mask for voxels set using minimum memory 6)Whats is a difference between process and thread 7)What is a difference between abstract class and interface 8)Given n unsorted time Intervals find the period of time with the maximum time intersections number 9)What is big endian/little endian systems.How is it possible to check what is an endian in you computer? 10)Projects description