format()の時間計算量を改善

[ikeyan]

format()関数のeditsを適用する計算量が、およそO(ソース文字列.length × edits.length)になっていたので、O(ソース文字列.length + edits.length * log(edits.length)) になるように変更しました。

[EduApps-CDG]

Translation:
Title:

Improved time complexity of format()

Message:

The computational complexity of applying the format() function's edits was
O(source string.length × edits.length),
changed to O(source string.length + edits.length * log(edits.length) )

[EduApps-CDG]

As i'm also having troubles with format() command.

But I still need to check what's causing a memory leak inside that command.