small test

[مسك الختام]

hi everybody

i find
.this logic test (on the net ofcourse ) which is given to children when applying for kindergarten
( i guess in Russia )
.
Guys, I have to be honest, I failed this test but how about you?

8809 = 6
7111 = 0
2172 = 0
6666 = 4
1111 = 0
3213 = 0
7662 = 2
9312 = 1
0000 = 4
2222 = 0
3333 = 0
5555 = 0
8193 = 3
8096 = 5
7777 = 0
9999 = 4
7756 = 1
6855 = 3
9881 = 5
5531 = 0

2581 = ?