Help c++ number combinations

[ben han solo]

how to get all the possible combinations for 4 digits from a 5 digit number.
i need a pair that has both 5 digits and four digits. their sum must be equal to a five digit user input.
i.e.
user input : 14690
output:
14690 has pairs 12345 + 2345
2345 came from 12345
lets say that x = 12345 and y =2345
besides y == x%10000
other formula can i have since if i use % and / i will have a lot of declarations

[JasperBraun]

Try it for yourself first and post about your problem. No one will do it for you.

[prestokeys]

-ask for user input num
-if num < 10000 or >= 100000, ask again
-loop i from 10000 to num - 1000 and check if num - i is between 1000 and 9999, and print i and num - i if so.