Euler 407
Merge branch 'master' of https://github.com/alxsoares/algorithms
Merge branch 'master' of https://github.com/alxsoares/algorithms
Merge branch 'master' of https://github.com/alxsoares/algorithms
Merge branch 'master' of https://github.com/alxsoares/algorithms
Merge branch 'master' of https://github.com/alxsoares/algorithms
Merge branch 'master' of https://github.com/alxsoares/algorithms
Merge branch 'master' of https://github.com/alxsoares/algorithms
Improving performance