added Prolog solutions

2 files changed, 53 insertions, 0 deletions

diff --git a/challenge-195/adam-russell/prolog/ch-1.p b/challenge-195/adam-russell/prolog/ch-1.p
new file mode 100644
index 0000000000..fbafd20a40
--- /dev/null
+++ b/challenge-195/adam-russell/prolog/ch-1.p
@@ -0,0 +1,13 @@
+code2digit(C, D):-
+    number_codes(D, [C]).
+
+special(N):-
+    number_codes(N, NCodes),
+    maplist(code2digit, NCodes, Digits),
+    sort(Digits, DigitsSorted),
+    length(Digits, NumberDigits),
+    length(DigitsSorted, NumberDigits).
+
+number_special(N, NumberSpecial):-
+    findall(I, (between(1, N, I), special(I)), Specials),
+    length(Specials, NumberSpecial). 
diff --git a/challenge-195/adam-russell/prolog/ch-2.p b/challenge-195/adam-russell/prolog/ch-2.p
new file mode 100644
index 0000000000..8af05aeacc
--- /dev/null
+++ b/challenge-195/adam-russell/prolog/ch-2.p
@@ -0,0 +1,40 @@
+even(N, Even):-
+    (0 is mod(N, 2), Even = N);
+    (Even = nil).
+
+frequency(ListNumbers, N, Frequency):-
+    delete(ListNumbers, N, ListDeleted),
+    length(ListNumbers, L),
+    length(ListDeleted, LD),
+    Frequency is L - LD. 
+
+most_frequent_even(ListNumbers, MostFrequentEven):-
+    maplist(even, ListNumbers, EN),
+    delete(EN, nil, EvenNumbers), 
+    length(EvenNumbers, LengthEvens),
+    LengthEvens > 0,
+    maplist(frequency(ListNumbers), EvenNumbers, Frequencies),      
+    msort(Frequencies, FS), 
+    reverse(FS, FrequenciesSorted), 
+    ((
+         nth(1, FrequenciesSorted, F1),
+         nth(2, FrequenciesSorted, F2), 
+         F1 \== F2,
+         nth(N, Frequencies, F1),  
+         nth(N, EvenNumbers, MostFrequentEven)  
+     );
+     (
+         nth(1, FrequenciesSorted, F1),
+         nth(2, FrequenciesSorted, F2), 
+         F1 == F2,
+         nth(N1, Frequencies, F1),  
+         nth(N2, Frequencies, F2),  
+         nth(N1, EvenNumbers, MostFrequentEven1),  
+         nth(N2, EvenNumbers, MostFrequentEven2),    
+         ((MostFrequentEven1 < MostFrequentEven2, MostFrequentEven = MostFrequentEven1);  
+          (MostFrequentEven1 > MostFrequentEven2, MostFrequentEven = MostFrequentEven2))
+     ) 
+    ), !.
+
+most_frequent_even(_, MostFrequentEven):-
+    MostFrequentEven = -1, !.