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  1. program :- get_char(X),get_char(Y),check(X,Y). 
  2. check('4','2'):-!. 
  3. check(X,Y):-write(X),get_char(Z),check(Y,Z).
  4. :- program.
Success #stdin #stdout 0.02s 68352KB
comments (?)
stdin 
1
2
10
9
0
10
42
stdout 
GNU Prolog 1.3.1
By Daniel Diaz
Copyright (C) 1999-2009 Daniel Diaz
uncaught exception: error(syntax_error('user_input:2 (char:1) . or operator expected after expression'),read_term/3)
https://ideone.com/M7u0O
language:
Prolog (gprolog 1.4.5)
created:
14 years ago
visibility:
public

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