/**
 * cityHash实现
 * @param {string} s 需要计算hash的字符串
 */
export default function cityHash32(s) {
  const seed = 0;
  const len = s.length;
  let h = len;
  let g = seed;
  let f = 0;

  for (let i = 0; i < len; i++) {
    f += s.charCodeAt(i);
    g += f;
    h ^= g;
    g = ((g << 10) | (g >>> (32 - 10))) >>> 0;
    g = ((g + f) >>> 0) * 9 >>> 0;
  }

  h ^= g;
  h = ((h ^ (h >>> 16)) >>> 0) * 0x85ebca6b >>> 0;
  h = ((h ^ (h >>> 13)) >>> 0) * 0xc2b2ae35 >>> 0;
  h ^= h >>> 16;

  return h >>> 0;
}