Accelerating N-queens problem using OpenMP

Abstract

Backtracking algorithms are used to methodically and exhaustively search a solution space for an optimal solution to a given problem. A classic example of a backtracking algorithm is illustrated by finding all solutions to the problem of placing N-queens on an N × N chess board such that no two queens attack each other. This paper demonstrates a methodology for rewriting this backtracking algorithm to take advantage of multi-core computing resources. We accelerated a sequential version of the N-queens problem on ×86 and PPC64 architectures. Using problem sizes between 13 and 17, we observed an average speedup of 3.24 for ×86 and 9.24 for the PPC64.