# 93. Generate Fibonacci Number with recursion

JavaScriptShare

easy - accepted / - tried

In 86. Generate Fibonacci Number you are asked to create a `fib(n)`

.

This could be simply done by a recursion, but it costs so much time that your browser freezes, don't try it with large numbers.

```
const fib = (n) => {
if (n === 0) return 0
if (n === 1) return 1
return fib(n - 1) + fib(n - 2)
}
fib(10) // 55
fib(1000) // timeout
```

Can you improve above implementation to make it work for `fib(1000)`

? recursion should still be used.