Duplicate Encoder?

6 kyu

題目描述

Description

The goal of this exercise is to convert a string to a new string where each character in the new string is "(" if that character appears only once in the original string, or ")" if that character appears more than once in the original string. Ignore capitalization when determining if a character is a duplicate.

"din"      =>  "((("
"recede"   =>  "()()()"
"Success"  =>  ")())())"
"(( @"     =>  "))(("

Notes

Assertion messages may be unclear about what they display in some languages. If you read "...It Should encode XXX", the "XXX" is the expected result, not the input!

解答

Solution

function duplicateEncode(word) {
  const counter = {};
  word = word.toLowerCase();
  for (let i = 0; i < word.length; i++) {
    if (counter[word[i]] >= 1) {
      counter[word[i]] += 1;
    } else {
      counter[word[i]] = 1;
    }
  }

  result = "";

  for (let i = 0; i < word.length; i++) {
    result += counter[word[i]] === 1 ? "(" : ")";
  }

  return result;
}

解題思路

練習 counter 與把題目描述轉成 JS 程式碼

心得

題目滿簡單但我的答案滿醜ㄉ，應該能寫得更優雅！