10- rectangular footprint

We can use 2 small rectangle 1 of sideways or vertically to cover a larger rectangle. Will the n 2- small rectangle without overlapping cover 1 2 * n is a large rectangle, total number of ways

function rectCover(number)
{
    // write code here
    if(number < 3) return number;
    var pre = 1, cur = 2;
    for(var i = 2; i < number; i++) {
        cur = cur + pre;
        pre = cur - pre;
    }
    return cur
}