# Japt, 12 bytes

Takes input as a string, outputs an array of strings.

    Ë+pE
    ¬£h°YçX

[Try it](https://ethproductions.github.io/japt/?v=1.4.5&code=yytwRQqso2iwWedY&input=IjEyMzQiCi1S)

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## Explanation
                :Implicit input of string U
    Ë           :Map each character D at 0-based index E
      pE        :  Repeat D E times
     +          :  Append to D
    \n          :Reassign to U
    ¬           :Split to character array
     £          :Map each element X at 0-based index Y
       °Y       :  Increment Y
         çX     :  Repeat X Y times
      h         :  Replace the first Y characters in U with that