:- use_module(library(clpfd)).

knife(Sol) :-
   Vars = [K,N,I,F,E,O,R,S,P,U],
   Vars ins 0..9,
   Sol = sol(k:K,n:N,i:I,f:F,e:E,o:O,r:R,s:S,p:P,u:U),
   all_different(Vars),
   K #\=0, F #\= 0, S #\=0,
   K*10000 + N*1000 + I*100 + F*10 + E +
             F*1000 + O*100 + R*10 + K +
   S*10000 + P*1000 + O*100 + O*10 + N +
             S*1000 + O*100 + U*10 + P #=
   S*100000 + U*10000 + P*1000 + P*100 + E*10 + R,
   labeling([ff],Vars).