Leetcode

Kth Distinct String in an Array

May 26, 2022 by aAshish

  • Time:O(n)
  • Space:O(n)

C++

 
class Solution {
 public:
  string kthDistinct(vector<string>& arr, int k) {
    unordered_map<string, int> count;

    for (const string& a : arr)
      ++count[a];

    for (const string& a : arr)
      if (count[a] == 1 && --k == 0)
        return a;

    return "";
  }
};

JAVA

 
class Solution {
  public String kthDistinct(String[] arr, int k) {
    Map<String, Integer> count = new HashMap<>();

    for (final String a : arr)
      count.merge(a, 1, Integer::sum);

    for (final String a : arr)
      if (count.get(a) == 1 && --k == 0)
        return a;

    return "";
  }
}

Python

 
class Solution:
  def kthDistinct(self, arr: List[str], k: int) -> str:
    count = Counter(arr)

    for a in arr:
      if count[a] == 1:
        k -= 1
        if k == 0:
          return a

    return ''