First Unique Char in String — Easy DSA Problem

Problems/256. First Unique Char in String

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1def first_uniq_char(s):

2 counts = {}; q = []

3 for i, c in enumerate(s):

4 counts[c] = counts.get(c, 0) + 1

5 q.append((c, i))

6 while q and counts[q[0][0]] > 1:

7 q.pop(0)

8 return q[0][1] if q else -1

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