Generating number combinations

so i need to generate the numbers for the rows on a k-map for a user selected up to 10 total variables meaning 5 digits on the row headers, EX. user enters "4" for the total amount of variables and the program would display:

"00

01

11

00"

and im not so much confused on the programing side of it but more how to design a program to do this just looking for some helping ideas.

Is there maybe a way for the ser to enter the max number 5 and have the program generate all possible binary combinations for 5 binary bits? thats kinda what i have thinking so far

thanks guys.