First Unique Character in a String

Commonly asked at:Amazon Microsoft

Given a string, print the index of its first non-repeating character, or -1 if none exists.

Example

Input: leetcode Output: 0 (l never repeats and appears first)

Two passes with a hash map: first count every character's frequency, then scan again in order and return the first index whose count is 1.

Not solved yet

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Editor

s = input()
# TODO: count frequencies, then find first count==1
from collections import Counter
counts = Counter(s)

s = input()
# TODO: count frequencies, then find first count==1
from collections import Counter
counts = Counter(s)

Input (stdin)

Output

Run your code to see output here.

Isolated sandbox · not executed on your devicePowered by Judge0 CE (free, self-hosted). Runs in an isolated sandbox — not on your device.

Editor

s = input()
# TODO: count frequencies, then find first count==1
from collections import Counter
counts = Counter(s)

s = input()
# TODO: count frequencies, then find first count==1
from collections import Counter
counts = Counter(s)

Input (stdin)

Output

Run your code to see output here.

Isolated sandbox · not executed on your devicePowered by Judge0 CE (free, self-hosted). Runs in an isolated sandbox — not on your device.

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