介绍

在信息论中，两个等长字符串之间的汉明距离（英语：Hamming distance）是两个字符串对应位置的不同字符的个数。换句话说，它就是将一个字符串变换成另外一个字符串所需要替换的字符个数。

汉明重量是字符串相对于同样长度的零字符串的汉明距离，也就是说，它是字符串中非零的元素个数：对于二进制字符串（binary data strings）来说，就是 1 的个数，所以 11101 的汉明重量是 4。

实现

JavaScript

/**
 * Hamming Distance: https://en.wikipedia.org/wiki/Hamming_distance
 *
 *
 * Hamming distance is a metric（公式） for comparing two binary data strings.
 *
 * While comparing two binary strings of equal length, Hamming distance
 * is the number of bit positions in which the two bits are different.
 * The Hamming distance between two strings, a and b is denoted（记为） as d(a,b)
 */

/**
 * @param {string} a
 * @param {string} b
 * @return {number}
 */

const hammingDistance = (a, b) => {
 if (a.length !== b.length) {
  throw new Error("Strings must be of the same length");
 }

 let distance = 0;

 for (let i = 0; i < a.length; i += 1) {
  if (a[i] !== b[i]) {
   distance += 1;
  }
 }

 return distance;
};

参考

• Hamming distance - Wikiwand (opens new window)
• 汉明距离 - Wikiwand (opens new window)