hof6.html

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    <script>
        function memo(fn) {
            var cache = {};
            return function(args) {
                if(!cache[args]) {
                    cache[args] = fn(args);
                }
                return cache[args];
            }
        }

        function fibanocci(num) {
            return (num == 0 || num == 1)? num : fibanocci(num - 1) + fibanocci(num - 2);
        }

        var memFib = memo(fibanocci); // Closure --> fn : fibanocci and cache: {}
        console.time("first");
            console.log(memFib(34));
        console.timeEnd("first");

        console.time("second");
            console.log(memFib(34));
        console.timeEnd("second");

    </script>
</body>
</html>