interview prep 1.

findParenPosition.js

// I like parentheticals (a lot).

// "Sometimes (when I nest them (my parentheticals) too much (like this (and this))) they get confusing."

// Write a function that, given a sentence like the one above, along with the position of an opening parenthesis, finds the corresponding closing parenthesis.

// Example: if the example string above is input with the number 10 (position of the first parenthesis), the output should be 79 (position of the last parenthesis).


const findParenPosition = (string, pos) => {
  let openStack  = [pos];
  let closeStack = [];
  let scanPosition = pos + 1; 
  while (openStack.length !== 0) {
    if (string[scanPosition] === '(') {
      openStack.push(scanPosition)
    } else if (string[scanPosition] === ')') {
      closeStack.push(scanPosition)
    };
    if (closeStack.length === 1 && openStack.length === 1) {
      break;
    } else if (closeStack.length && openStack.length) {
      openStack.pop();
      closeStack.pop();
    };
    scanPosition++;
  };
  return closeStack[0];
};

const string1 = "Sometimes (when I nest them (my parentheticals) too much (like this (and this))) they get confusing.";

findParenPosition(string1, 10)