You may already heard of a backtracking algorithm called N-Queen problem. If not, please refer below link[0] to understand what kind of algorithm it is. 

1. Your first task is to develop a program that solves this N-Queen problem in an optimized way.
2. Then, design a user interface (web interface with Jquery/HTML5 would be an ideal answer) that can generate an on-demand chess-board (2D board will suffice) in terms of user input (number of ranks/files). 
3. Link your algorithm solution code with the your designed UI so that a user can play them game by placing all queens in non-attacking positions by number of minimum movements.

PS : Please contact the mentor, if you have any clarifications regarding the algorithm or the intention of the game.

[0] - http://www.math.utah.edu/~alfeld/queens/queens.html