JS 字符串操作面试题 about frontend-interview HOT 34 OPEN

function foo(str1, str2) {
  return !str1.split('').sort().join('').replace(str2.split('').sort().join(''), '');
}

function isMatch(str1, str2) {
  if (typeof str1 !== 'string' || typeof str2 !== 'string') return false;
  if (str1 === '' && str2 === '') return true;
  if (str1.length !== str2.length) return false;

  var strCollection1 = getCollection(str1);
  var strCollection2 = getCollection(str2);

  return collectionsAreEqual(strCollection1, strCollection2);
}

/**
 * Return the collection of numbers of each letter in str
 * Example input: "hello"
 * Example output:
 * {
 *   “h“: 1,
 *   "e": 1,
 *   "l": 2,
 *   "o": 1
 * }
 */
function getCollection(str) {
}

/**
 * Return true if collections are equal, otherwise false
 */
function collectionsAreEqual(collection1, collection2) {
}

function isMatch(str1, str2) {
  var len1 = str1.length,len2=str2.length;
  if (len1 !== len2)return false;
  for (var i=0;i<len1 ; i++){
      if (str1[i] !== str2[len1-i-1]){
          return false;
      }
  }
  return true;
}

function isMatch(str1, str2) {
	if (typeof str1 !== 'string' || typeof str2 !== 'string') return false;
	if (str1 === str2) return true;
	if (str1.length !== str2.length) return false;
	
	var str1Collection = getCollection(str1),
		str2Collection = getCollection(str2);

	return collectionAreEqual(str1Collection, str2Collection);
}

function getCollection(str) {
	var collection = {};
	for (var i = 0, len = str.length; i < len; ++i) {
		if (collection[str[i]] === undefined) {
			collection[str[i]] = 0
		} else {
			collection[str[i]]++;
		}
	}
	return collection;
}

function collectionAreEqual(collection1, collection2) {
	var keys1 = Object.keys(collection1),
	      keys2 = Object.keys(collection2);
	
	if (keys1.length !== keys2.length) return false;
	for (var key in collection1) {
		if (collection1[key] !== collection2[key]) {
			return false;
		}
	}
	return true;
}

if (collection[str[i]] == null) {

function isMatch(str1, str2) {
  if (typeof str1 !== 'string' || typeof str2 !== 'string') return false;
  if (str1 === str2) return true;
  if (str1.length !== str2.length) return false;

  const count_map = {}; // 记录每个字符出现次数

  for (let i = 0; i < str1.length; i++) {
    if (str1[i] in count_map)
      count_map[str1[i]]++;
    else
      count_map[str1[i]] = 1;
  }

  for (let i = 0; i < str2.length; i++) {
    if (!(str2[i] in count_map) ||
      --count_map[str2[i]] < 0
    )
      return false;
  }
  return true;
}

console.log(isMatch('something', 'ginhtemos'));
console.log(isMatch('aaa', 'aa'));
console.log(isMatch('abb', 'baa'));
console.log(isMatch('hello', 'olelh'));

let string1 = (Math.random() * 1e64).toString(36)
let string2 = string1 + 'test'
let string3 = 'test' + string1
let string4 = 'aaaa' + string1

function isMatch1 (str1, str2) {
  if (str1 === str2) return true
  if (str1.length !== str2.length) return false
  for (let key in str1) {
    str2 = str2.replace(str1[key], '')
  }
  if (str2.length === 0) {
    return true
  }
  return false
}

function isMatch (str1, str2) {
  if (str1 === str2) return true
  if (str1.length !== str2.length) return false

  let hash1 = getHash(str1)
  let hash2 = getHash(str2)

  if (hash1.length !== hash2.length) return false
  for (let key in hash1) {
    if (hash1[key] !== hash2[key]) return false
  }
  return true
}

function getHash (str) {
  let hash = {}
  for (let i = 0, k = str.length; i < k; i++) {
    hash[ str[i] ] ? hash[ str[i] ]++ : hash[ str[i] ] = 1
  }
  return hash
}

function isMatch2 (str1, str2) {
  return str1.split('').sort().join('') === str2.split('').sort().join('')
}

console.time('isMatch')
for (let i = 0; i < 10000; i++) {
  isMatch(string2, string3)
  isMatch(string3, string4)
}
console.timeEnd('isMatch')

console.time('isMatch1')
for (let i = 0; i < 10000; i++) {
  isMatch1(string2, string3)
  isMatch1(string3, string4)
}
console.timeEnd('isMatch1')

console.time('isMatch2')
for (let i = 0; i < 10000; i++) {
  isMatch2(string2, string3)
  isMatch2(string3, string4)
}
console.timeEnd('isMatch2')