找到差异使用javascript

时间:2016-08-29 16:20:41

标签: javascript hashtable

这是一个leetcode问题。
给定两个字符串s和t,它们只包含小写字母。

字符串t由随机混洗字符串s生成,然后在随机位置再添加一个字母。

找到t中添加的字母。

https://leetcode.com/problems/find-the-difference/
我正在尝试使用哈希表,但似乎我错了。

var findTheDifference = function(s, t) {
var hashTable = {};
var array = s.split('');
   array.forEach(function (element) {
   hashTable[element] = element;
   });
   for( var i = 0; i < t.length; i++) {
      if(!hashTable.hasOwnProperty(t.charAt(i))) {
         return t.charAt(i);
      }
  }
};


这个错误的代码可以传递样本输入:

Input:
s = "abcd"
t = "abcde"

Output:
e

但是对于大字符串将是错误的

Input :"ymbgaraibkfmvocpizdydugvalagaivdbfsfbepeyccqfepzvtpyxtbadkhmwmoswrcxnargtlswqemafandgkmydtimuzvjwxvlfwlhvkrgcsithaqlcvrihrwqkpjdhgfgreqoxzfvhjzojhghfwbvpfzectwwhexthbsndovxejsntmjihchaotbgcysfdaojkjldprwyrnischrgmtvjcorypvopfmegizfkvudubnejzfqffvgdoxohuinkyygbdzmshvyqyhsozwvlhevfepdvafgkqpkmcsikfyxczcovrmwqxxbnhfzcjjcpgzjjfateajnnvlbwhyppdleahgaypxidkpwmfqwqyofwdqgxhjaxvyrzupfwesmxbjszolgwqvfiozofncbohduqgiswuiyddmwlwubetyaummenkdfptjczxemryuotrrymrfdxtrebpbjtpnuhsbnovhectpjhfhahbqrfbyxggobsweefcwxpqsspyssrmdhuelkkvyjxswjwofngpwfxvknkjviiavorwyfzlnktmfwxkvwkrwdcxjfzikdyswsuxegmhtnxjraqrdchaauazfhtklxsksbhwgjphgbasfnlwqwukprgvihntsyymdrfovaszjywuqygpvjtvlsvvqbvzsmgweiayhlubnbsitvfxawhfmfiatxvqrcwjshvovxknnxnyyfexqycrlyksderlqarqhkxyaqwlwoqcribumrqjtelhwdvaiysgjlvksrfvjlcaiwrirtkkxbwgicyhvakxgdjwnwmubkiazdjkfmotglclqndqjxethoutvjchjbkoasnnfbgrnycucfpeovruguzumgmgddqwjgdvaujhyqsqtoexmnfuluaqbxoofvotvfoiexbnprrxptchmlctzgqtkivsilwgwgvpidpvasurraqfkcmxhdapjrlrnkbklwkrvoaziznlpor"


"qhxepbshlrhoecdaodgpousbzfcqjxulatciapuftffahhlmxbufgjuxstfjvljybfxnenlacmjqoymvamphpxnolwijwcecgwbcjhgdybfffwoygikvoecdggplfohemfypxfsvdrseyhmvkoovxhdvoavsqqbrsqrkqhbtmgwaurgisloqjixfwfvwtszcxwktkwesaxsmhsvlitegrlzkvfqoiiwxbzskzoewbkxtphapavbyvhzvgrrfriddnsrftfowhdanvhjvurhljmpxvpddxmzfgwwpkjrfgqptrmumoemhfpojnxzwlrxkcafvbhlwrapubhveattfifsmiounhqusvhywnxhwrgamgnesxmzliyzisqrwvkiyderyotxhwspqrrkeczjysfujvovsfcfouykcqyjoobfdgnlswfzjmyucaxuaslzwfnetekymrwbvponiaojdqnbmboldvvitamntwnyaeppjaohwkrisrlrgwcjqqgxeqerjrbapfzurcwxhcwzugcgnirkkrxdthtbmdqgvqxilllrsbwjhwqszrjtzyetwubdrlyakzxcveufvhqugyawvkivwonvmrgnchkzdysngqdibhkyboyftxcvvjoggecjsajbuqkjjxfvynrjsnvtfvgpgveycxidhhfauvjovmnbqgoxsafknluyimkczykwdgvqwlvvgdmufxdypwnajkncoynqticfetcdafvtqszuwfmrdggifokwmkgzuxnhncmnsstffqpqbplypapctctfhqpihavligbrutxmmygiyaklqtakdidvnvrjfteazeqmbgklrgrorudayokxptswwkcircwuhcavhdparjfkjypkyxhbgwxbkvpvrtzjaetahmxevmkhdfyidhrdeejapfbafwmdqjqszwnwzgclitdhlnkaiyldwkwwzvhyorgbysyjbxsspnjdewjxbhpsvj"

感谢任何建议~~~~

2 个答案:

答案 0 :(得分:1)

您可以使用哈希表进行计数。为原始字符串中的每个字母添加一个,并为操作字符串中的每个字母减去一个字母。然后只取非空的哈希值。

{{1}}

答案 1 :(得分:1)

一种方法是对字符串进行排序,然后找出它们之间的第一个区别:

var str = "1122334477422";
var str2 = "15122332247744";
var sorted = str.split('').sort();
var sorted2 = str2.split('').sort()
for(var i = 0; i< sorted2.length; i++){
    if(i == sorted2.length || sorted[i] != sorted2[i]){
        alert(sorted2[i]);
        break;
    }
}