numericals-of-a-string

Numericals of a String

You are given an input string.

For each symbol in the string if it's the first character occurrence, replace it with a '1', else replace it with the amount of times you've already seen it...

But will your code be performant enough?

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Examples:

input   =  "Hello, World!"
result  =  "1112111121311"

input   =  "aaaaaaaaaaaa"
result  =  "123456789101112"

There might be some non-ascii characters in the string.

Note: there will be no int domain overflow (character occurrences will be less than 2 billion).