Remove space-padding from <pre> blocks

1 files changed, 4 insertions, 4 deletions

diff --git a/prolog/problems/lists/conc_3/en.py b/prolog/problems/lists/conc_3/en.py
index 7399f7e..ba1a571 100644
--- a/prolog/problems/lists/conc_3/en.py
+++ b/prolog/problems/lists/conc_3/en.py
@@ -6,10 +6,10 @@ slug = 'concatenate two lists'
 description = '''\
 <p><code>conc(L1, L2, L)</code>: the list <code>L</code> is obtained by appending the elements of <code>L2</code> to <code>L1</code>.</p>
 <pre>
-  ?- conc([1,2], [3,4], X).
-    X = [1,2,3,4].
-  ?- conc(X, [], [1,2,3]).
-    X = [1,2,3].
+?- conc([1,2], [3,4], X).
+  X = [1,2,3,4].
+?- conc(X, [], [1,2,3]).
+  X = [1,2,3].
 </pre>'''
 
 hint = {}