I feel nowadays to meaningfully talk about performance of N-queens problem N should start with 18 instead of 8.. Here is a C++ solution with 40 lines of code and can solve 18-queens in less than a minute on a laptop:
Are you calculating the total number of solutions, or just finding a solution? The latter has a closed form solution: https://gist.github.com/IanCal/1858601
That'll do ~N=1e6 in a second (I'm sure there are lots of optimisations that could be done in it though), or solutions for N=4 to N=1000 in less than 10.
The more complex problem is finding out how many solutions there are in total.
Apologies, I'm posting this few times, but are you calculating the total number of solutions, or just finding a solution? The latter has a closed form solution: https://gist.github.com/IanCal/1858601
That'll do ~N=1e6 in a second (I'm sure there are lots of optimisations that could be done in it though), or solutions for N=4 to N=1000 in less than 10.
The more complex problem is finding out how many solutions there are in total.
https://gist.github.com/jdeng/7915749