First Unique Character in a String

Get all indexes of characters in the string.

Can use array and ascii number instead.
If the length of indexes is 1, collect the index.
Find the minimum of them.
```
def firstUniqChar(self, s):
 """
 :type s: str
 :rtype: int
 """
 dic = collections.defaultdict(list)
 for i, c in enumerate(s):
     dic[c].append(i)
    
 values = []
 for l in dic.values():
     if len(l) == 1:
         values += l
            
 return min(values) if values else -1
```
Solution - Faster

It’s faster because s.index is a C function that python is calling. So the python loop is changed to be the 26 characters, and the C loop is doing the heavy lifting searching the string. From an algo perspective this is slower than the others. But good to know for python users for runtime speedup. ```python def firstUniqChar(self, s): “”” :type s: str :rtype: int “””

letters=’abcdefghijklmnopqrstuvwxyz’ index=[s.index(l) for l in letters if s.count(l) == 1] return min(index) if len(index) > 0 else -1 ```