Converting string to int without atoi and stringstream

[apa125]

Hi guys,
I wonder if there is a way to convert string to int without atoi and stringstream.
Am I going to convert C-string to an array of int ?

[vlad from moscow]

If atoi does the task then why do you wonder? It is obvious that atoi uses some way to convert a string to an integer that you can reproduce.

[apa125]

I wonder if I can write a program and convert it by myself.

[3qX21hU5]

http://www.asciitable.com/ use ascii but don't see why you would reinvent the wheel unless it is for a learning experience. Stringstream is probably the best way to go about it.