danedavid

// returns an array containing all permutations of a given string
const permute = str => {
  let permutations = [];

  if ( str.length <= 1 ) {
    return [str];
  }

  for ( let i = 0; i < str.length; i++ ) {
    let char = str[i];

danedavid

const isBalanced = str => {
  const arr = str.split('');
  const res = arr.reduce((acc, item) => {
    if ( acc.slice(-1)[0] === '(' ) {
      if ( item === ')' ) {
        acc.pop();
        return acc;
      }
    }
    if ( item === '(' || item === ')' ) {