Construct string via recursion JavaScript

We are required to write a recursive function, say pickString that takes in a string that contains a combination of alphabets and numbers and returns a new string consisting of only alphabets.

For example,

If the string is ‘dis122344as65t34er’,
The output will be: ‘disaster’

Therefore, let’s write the code for this recursive function −

Example

const str = 'ex3454am65p43le';
const pickString = (str, len = 0, res = '') => {
   if(len < str.length){
      const char = parseInt(str[len], 10) ? '' : str[len];
      return pickString(str, len+1, res+char);
   };
   return res;
};
console.log(pickString(str));
console.log(pickString('23123ca43n y43ou54 6do884 i43t'));
console.log(pickString('h432e54l43l65646o'));
console.log(pickString('t543h54is 54i5s 54t43he l543as53t
54ex87a455m54p45le'));

Output

The output in the console will be −

example
can you do it
hello
this is the last example