An Array Of Zeroes
November 21, 2014
Beware! Today’s exercise, which derives from an interview question asked at Facebook, is trickier than it looks:
You are given an array of integers. Write a program that moves all non-zero integers to the left end of the array, and all zeroes to the right end of the array. Your program should operate in place. The order of the non-zero integers doesn’t matter. As an example, given the input array [1,0,2,0,0,3,4], your program should permute the array to [1,4,2,3,0,0,0] or something similar, and return the value 4.
Your task is to write the indicated program. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.
Programming Praxis 