Loops with smarter backtracking

We've now improved our loops by using while…and are able to backtrack in our columns,…but in the process of doing that we discovered…that we also need more control…over looping through the rows as well.…Once again I've added a new file…to our code clinic project.…This one is called loop3.rb.…You can see that most of the code looks exactly the same.…The changes are all inside this function here,…solve queens problem.…Notice that I had column equals zero before…and I was looping through columns by using…while columns is less than the total columns.…

Now I'm going to add a new line,…row equals zero, and while row is…less than the total number of rows,…we're going to keep performing the loop…and we're going to make sure that we also…increment the row down here.…If we're not at the ending row yet,…then row plus equals one.…This is the substantive changes…except for this section right here.…So this will work.…This will allow us to loop through.…When we get to a column that doesn't work…and we need to backtrack, it's going to loop back up here…