[ubuntu] Want to reinstall Ubuntu beside Windows 7 topic

Hi

i had 2 OS. Windows 7 and Ubuntu 13.10 side by side. On the start I used to choose windows7 or Ubuntu.
yesterday I accidentally uninstalled Ubuntu OS.
i did system restore but could not get back Ubuntu OS.
now I have Windows 7
i checked from computer management that it has
C drive which has Windows7
F drive which has Ubuntu

Now, how can I renstall/recover Ubuntu OS like before from the Hard drive?
please reply to my email also: albaqui@gmail.com