text: import { NotImplementedError } from '../extensions/index.js';
  
  /**
   * Given two strings, find the number of common characters between them.
   *
   * @param {String} s1
   * @param {String} s2
   * @return {Number}
   *
   * @example
   * For s1 = "aabcc" and s2 = "adcaa", the output should be 3
   * Strings have 3 common characters - 2 "a"s and 1 "c".
   */
  export default function getCommonCharacterCount( s1, s2 ) {
    const map = {};
    let res = 0;
  
    for (let sym of s1) {
      if (sym in map) {
        map[sym] += 1;
      } else {
        map[sym] = 1;
      }
    }
  
    for (let sym2 of s2) {
      if (sym2 in map && map[sym2] > 0) {
        res += 1;
        map[sym2] -= 1;
      } else {
  
      }
    }
  
    return res;
  }
  