1 files changed, 17 insertions, 0 deletions

diff --git a/2019/day4/password.lp b/2019/day4/password.lp
new file mode 100644
index 0000000..b9a1f1a
--- /dev/null
+++ b/2019/day4/password.lp
@@ -0,0 +1,17 @@
+%353096-843212
+digit(X) :- X = 0..9.
+place(N) :- N = 1..6.
+
+1 {pass(Q,X) : digit(X)} 1 :- place(Q).
+value(N) :- N = A + B * 10 + C * 100 + D * 1000 + E * 10000 + F * 100000, pass(6,A), pass(5,B), pass(4,C), pass(3,D), pass(2,E), pass(1,F).
+
+:- value(N), N < 353096.
+:- value(N), N > 843212.
+
+:- pass(Q,X), pass(Q', Y), Q' = Q + 1, X > Y.
+%:- pass(Q,X), pass(Q', Y), pass(QQ, Z), Q' = Q + 1, QQ = Q' + 1, X = Y, Y = Z. % I couldn't figure out this so I did 581 - 2
+
+%1 {target(X,Y,XX,YY) : dir(DX,DY), XX-X = DX*S, YY-Y = DY*S, size(S), area(XX,YY,_)} 1 :- number(X,Y,_).
+
+#show pass/2.
+#show value/1.