Cryptarithmetic puzzles consist of a mathematical equation whose digits are represented by letters of the alphabet. The goal is to identify the value of each letter.
Examples
send_more_money([S,E,N,D],[M,O,R,E],[M,O,N,E,Y]) :-
Vars = [S,E,N,D,M,O,R,Y],
Vars ins 0..9,
S #\= 0,
M #\= 0,
all_different(Vars),
1000*S + 100*E + 10*N + D +
1000*M + 100*O + 10*R + E #=
10000*M + 1000*O + 100*N + 10*E + Y,
label(Vars).
?- send_more_money(Send,More,Money).
Money = [1,0,6,5,2]
More = [1,0,8,5]
Send = [9,5,6,7]
yes;
no donald_gerald_robert([D,O,N,A,L,D],[G,E,R,A,L,D],[R,O,B,E,R,T]) :-
Vars = [D,O,N,A,L,G,E,R,B,T],
Vars ins 0..9,
all_different(Vars),
100000*D + 10000*O + 1000*N + 100*A + 10*L + D +
100000*G + 10000*E + 1000*R + 100*A + 10*L + D #=
100000*R + 10000*O + 1000*B + 100*E + 10*R + T,
label(Vars).
?- donald_gerald_robert(Donald,Gerald,Robert).
Donald = [5,2,6,4,8,5]
Gerald = [1,9,7,4,8,5]
Robert = [7,2,3,9,7,0]
yes;
no