input = """

a(X,Y) :- c(X,R,S), d(S,T,Y), not na(X,Y).
na(X,Y) :- c(X,R,S), d(S,T,Y), not a(X,Y).

c(z,r,a).
c(z,s,a).

d(a,r,y).
d(a,s,y).

"""
output = """

a(X,Y) :- c(X,R,S), d(S,T,Y), not na(X,Y).
na(X,Y) :- c(X,R,S), d(S,T,Y), not a(X,Y).

c(z,r,a).
c(z,s,a).

d(a,r,y).
d(a,s,y).

"""

input = """

a(X,Y) :- c(X,R,S), d(S,T,Y), not na(X,Y).
na(X,Y) :- c(X,R,S), d(S,T,Y), not a(X,Y).

c(z,r,a).
c(z,s,a).

d(a,r,y).
d(a,s,y).

"""
output = """

a(X,Y) :- c(X,R,S), d(S,T,Y), not na(X,Y).
na(X,Y) :- c(X,R,S), d(S,T,Y), not a(X,Y).

c(z,r,a).
c(z,s,a).

d(a,r,y).
d(a,s,y).

"""

a(X,Y) :- c(X,R,S), d(S,T,Y), not na(X,Y).
 na(X,Y) :- c(X,R,S), d(S,T,Y), not a(X,Y).
 
 c(z,r,a).
 c(z,s,a).
 
 d(a,r,y).
 d(a,s,y). a(X,Y) :- c(X,R,S), d(S,T,Y), not na(X,Y).
 na(X,Y) :- c(X,R,S), d(S,T,Y), not a(X,Y).
 
 c(z,r,a).
 c(z,s,a).
 
 d(a,r,y).
 d(a,s,y).