Fibonacci - non recursive solution

fibonacci.js

fibonacci : function(n) {
    // f(0) = 0
    // f(1) = 1
    // f(n) = f(n-1) + f(n-2)
    if (n === 0) {
        return 0;
    }
    if (n === 1) {
        return 1;
    }
    
    var previous = 0;
    var current = 1;
    
    for (var i=2; i <=n; i++) {
        new_current = previous + current;
        previous = current;
        current = new_current;
    }
    
    return current;
}