In notepad++
You can try select all text/code, hit TAB and tab backwards with Shift+TAB.
Another thing you can try, install NppTextFX plugin, then select all text/code and use "TextFX->TextFX edit->Reindent C++ code" (I remember @Mitchell mention this in one of post)
*
from View-> Show symbols -> Show White spaces and TAB
*edit
uu what I found
[TUT][HQ] Indenting your code in proper way!