Add related problems

judge/ml/collab_filter.py

@@ -65,7 +65,7 @@ class CollabFilter:
         return res
 
     # return a list of pid
-    def problems_neighbors(self, problem, problemset, measure=DOT, limit=None):
+    def problem_neighbors(self, problem, problemset, measure=DOT, limit=None):
         pid = problem.id
         if pid >= len(self.problem_embeddings):
             return None
@@ -74,7 +74,7 @@ class CollabFilter:
         )
         res = []
         for p in problemset:
-            if p.id < len(scores):
-                res.append((scores[p.id], p))
+            if p < len(scores):
+                res.append((scores[p], p))
         res.sort(reverse=True, key=lambda x: x[0])
         return res[:limit]

judge/utils/problems.py

@@ -1,6 +1,8 @@
 from collections import defaultdict
 from math import e
 import os, zipfile
+from datetime import datetime
+import random
 
 from django.conf import settings
 from django.core.cache import cache
@@ -10,6 +12,8 @@ from django.utils import timezone
 from django.utils.translation import gettext as _, gettext_noop
 
 from judge.models import Problem, Submission
+from judge.ml.collab_filter import CollabFilter
+
 
 __all__ = [
     "contest_completed_ids",
@@ -229,3 +233,20 @@ def hot_problems(duration, limit):
 
         cache.set(cache_key, qs, 900)
     return qs
+
+
+def get_related_problems(profile, problem, limit=8):
+    if not profile:
+        return None
+    problemset = Problem.get_visible_problems(profile.user).values_list("id", flat=True)
+    problemset = problemset.exclude(id__in=user_completed_ids(profile))
+    problemset = problemset.exclude(id=problem.id)
+    cf_model = CollabFilter("collab_filter")
+    results = cf_model.problem_neighbors(
+        problem, problemset, CollabFilter.DOT, limit
+    ) + cf_model.problem_neighbors(problem, problemset, CollabFilter.COSINE, limit)
+    results = list(set([i[1] for i in results]))
+    seed = datetime.now().strftime("%d%m%Y")
+    random.Random(seed).shuffle(results)
+    results = results[:limit]
+    return [Problem.objects.get(id=i) for i in results]

judge/views/problem.py

@@ -76,6 +76,7 @@ from judge.utils.problems import (
     hot_problems,
     user_attempted_ids,
     user_completed_ids,
+    get_related_problems,
 )
 from judge.utils.strings import safe_float_or_none, safe_int_or_none
 from judge.utils.tickets import own_ticket_filter
@@ -352,6 +353,10 @@ class ProblemDetail(
         else:
             context["fileio_input"] = None
             context["fileio_output"] = None
+        if not self.in_contest:
+            context["related_problems"] = get_related_problems(
+                self.profile, self.object
+            )
 
         return context