2x+4y=94 (feet)

X+y=35 (head)

Get x=23.

y= 12

So the password is either 23 12 or 1223, and the last password is 23 12.

Bao Beier's calculation method is that if two feet are lifted, 94-35*2=24, then the rabbit has two feet, and 24/2= 12, so the rabbit is 12 and the chicken is 23.