30-seconds-of-code/snippets/sdbm.md

title, tags, expertise, cover, firstSeen, lastUpdated

title	tags	expertise	cover	firstSeen	lastUpdated
Hash string into number	math	intermediate	blog_images/dark-leaves.jpg	2017-12-27T17:12:34+02:00	2020-10-22T20:24:30+03:00

Hashes the input string into a whole number.

• Use String.prototype.split() and Array.prototype.reduce() to create a hash of the input string, utilizing bit shifting.

const sdbm = str => {
  let arr = str.split('');
  return arr.reduce(
    (hashCode, currentVal) =>
      (hashCode =
        currentVal.charCodeAt(0) +
        (hashCode << 6) +
        (hashCode << 16) -
        hashCode),
    0
  );
};

sdbm('name'); // -3521204949