How to decode a six-digit number algorithm into a four-digit one?

K

kos_by2014-11-22 16:16:03

Encryption

kos_by, 2014-11-22 16:16:03

For example, there is a five or six-digit number that is encrypted into a four-digit number. You need to find an encryption algorithm and pick up a four-digit code for the last three six-digit digits.
Here are examples:
030265- 1244
056495- 1244
234065- 1244
011943- 2658
081833-
2658
002442- 4969
041166- 4969
143178- 4969
084534- 7103
228992- 7103
560686- 7103
000049-
000666-?
085459-?