Words to Num

words2num.js

const wordsToNumMap = {
  zero: 0,
  one: 1,
  two: 2,
  three: 3,
  four: 4,
  five: 5,
  six: 6,
  seven: 7,
  eight: 8,
  nine: 9,
  ten: 10,
  eleven: 11,
  twelve: 12,
  thirteen: 13,
  fourteen: 14,
  fifteen: 15,
  sixteen: 16,
  seventeen: 17,
  eighteen: 18,
  nineteen: 19,
  twenty: 20,
  thirty: 30,
  fourty: 40,
  fifty: 50,
  sixty: 60,
  seventy: 70,
  eighty: 80,
  ninety: 90,
  hundred: 100,
  thousand: 1e3,
  million: 1e6,
  billion: 1e9,
  trillion: 1e12,
};


function wordsToNum(str) {
  console.info(str);

  const nums = str
    .trim()
    .replace(/[^a-zA-Z ]/g, ``)
    .split(/\s+/)
    .map(word => wordsToNumMap[word]);

  let result = 0;
  let segmentResult = 0;

  for (const num of nums) {
    if (num < 100) {
      segmentResult += num;
    } else if (num === 100) {
      segmentResult *= num;
    } else {
      result += segmentResult * num;
      segmentResult = 0;
    }
  }

  result += segmentResult;
  console.info(result.toLocaleString());
}

wordsToNum(`
  one billion,
  two hundred thirty four million,
  five hundred sixty seven thousand,
  eight hundred ninety
`);

wordsToNum(`one billion six hundred thousand fourty four`);