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# First Unique Character in String

## Problem

Given a string, find the first non-repeating character in it and return its index. If it doesn't exist, return -1.

{% hint style="info" %}
For example:

```
s = "leetcode"
return 0.

s = "loveleetcode"
return 2.
```

{% endhint %}

## Solution

```
class Solution:
    def firstUniqChar(self, s: str) -> int:
        freq = {}
        
        if not s:
            return -1
        
        for i in s:
            if i not in freq:
                freq[i] = 0
            freq[i]+=1
        
        for i in range(len(s)):
            if freq[s[i]] == 1:
                return i
        return -1
```