387 - First Unique Character in a String

Details

Key	Value
Link	https://leetcode.com/problems/first-unique-character-in-a-string/
Language	Python 3
Runtime	170 ms, faster than 54.13% of Python3 online submissions for First Unique Character in a String
Memory Usage	14.2 MB, less than 59.00% of Python3 online submissions for First Unique Character in a String
Datastructures	str
Algorithms	Iteration
Complexity	Time: O(N) Memory: O(1)

Procedure

1. ...

Code

Option 1

class Solution:
    def firstUniqChar(self, s: str) -> int:                    
        d = {}
        for char in s: d[char] = d.get(char, 0) + 1
            
        for i, char in enumerate(s):
            if d[char] == 1: return i
        
        return -1

Option 2: One-Liner

class Solution:
    def firstUniqChar(self, s: str) -> int:                    
        return min(([s.index(char) for char in set(s) if s.count(char) == 1] or [-1]))