2 files changed, 31 insertions, 0 deletions
diff --git a/prolog/problems/clp_fd/tobase_3/common.py b/prolog/problems/clp_fd/tobase_3/common.py
new file mode 100644
index 0000000..fb88be0
--- /dev/null
+++ b/prolog/problems/clp_fd/tobase_3/common.py
@@ -0,0 +1,15 @@
+id = 150
+group = 'clp_fd'
+number = 62
+visible = True
+facts = None
+
+solution = '''\
+tobase(0, _, 0) :- !.
+tobase(N, B, Nb) :-
+  B in 2..10,
+  indomain(B),
+  N #= N1 * B + Rem,
+  Rem #>= 0, Rem #< B,
+  Nb #= Nb1 * 10 + Rem,
+  tobase(N1, B, Nb1).'''
diff --git a/prolog/problems/clp_fd/tobase_3/en.py b/prolog/problems/clp_fd/tobase_3/en.py
new file mode 100644
index 0000000..bac8723
--- /dev/null
+++ b/prolog/problems/clp_fd/tobase_3/en.py
@@ -0,0 +1,16 @@
+id = 150
+name = 'tobase/3'
+slug = 'convert numbers from/to the decimal system'
+
+description = '''\
+<p><code>tobase(Number, B, X)</code>: given a <code>Number</code> in the decimal system (base 10), <code>X</code> represents the same number in the system with base <code>B</code>. Implement this predicate using constraints. Limit the value of <code>B</code> to the interval [2..10].</p>
+<pre>
+  ?- tobase(42, 2, X).
+    X = 101010.
+  ?- tobase(N, 2, 101010).
+    N = 42.
+  ?- tobase(42, B, 101010).
+    B = 2.
+</pre>'''
+
+hint = {}