JavaScript - feynman_sq_question.txt

how many different squares are there in a grid of NxN squares?


- - - - - my solution - - - - -

function countSquares(n){
    solution = 0;
    for(var i = n; i > 0; i--) {
        solution = solution + Math.pow(i,2);
    }
    return solution;
}


- square every number between ’n’ and ‘1’ and add them together.


- - - alt - - -
this is a recursive solution.
not bad, but its simple enough that a strait forward solution seems to work just as well.
it returns n squared plus n-1 squared plus n-2 squares . . . til n === 1.


function countSquares(n){
  if (n === 1) return 1;
  return n*n + countSquares(n-1);
}