Write sumNumbers(value) that adds up every finite number found anywhere inside value, which may be a number, a string, null, an array, or an object whose values can again be any of these.
- Strings, booleans,
null and undefined are ignored: the string "5" is not a number - Numbers that are not finite (
NaN, Infinity) are ignored - The structure may contain a cycle (an object that contains itself): it must not recurse forever
- An array or object that is reachable by more than one route is counted once, not once per route
- Beware:
typeof null is "object"