[202102710 조서현] fix: priority_queue.py, main.py

.github/workflows/python-app.yml

@@ -41,4 +41,4 @@ jobs:
         pylint *.py
     - name: Test with pytest
       run: |
-        pytest
+        python test.py

main.py

@@ -1,14 +1,14 @@
 from priority_queue import PriorityQueue
 def main():
-    pq = PriorityQueue()
-  
-    pq.push("Task 1", 3)
-    pq.push("Task 2", 1)
-    pq.push("Task 3", 2)
-  
-    print(pq.pop())
-    print(pq.pop())
-    print(pq.pop())
+  pq = PriorityQueue()
+
+  pq.push("Task 1", 3)
+  pq.push("Task 2", 1)
+  pq.push("Task 3", 2)
+
+  print(pq.pop())
+  print(pq.pop())
+  print(pq.pop())
 
 if __name__ == "__main__":
-    main()
+  main()

priority_queue.py

@@ -10,11 +10,11 @@ def push(self, item, priority):
   def pop(self):
     if len(self.heap) > 1:
       self._swap(0, len(self.heap) - 1)
-      priority, item = self.heap.pop()
+      _, item = self.heap.pop()
       self._sift_down(0)
       return item
     elif len(self.heap) == 1:
-      priority, item = self.heap.pop()
+      _, item = self.heap.pop()
       return item
     else:
       return None
@@ -35,11 +35,11 @@ def _sift_down(self, index):
       smallest = index
 
       if left_child_index < len(self.heap) and \
-        self.heap[left_child_index][0] > self.heap[smallest][0]:
+        self.heap[left_child_index][0] < self.heap[smallest][0]:
         smallest = left_child_index
 
       if right_child_index < len(self.heap) and \
-        self.heap[right_child_index][0] > self.heap[smallest][0]:
+        self.heap[right_child_index][0] < self.heap[smallest][0]:
         smallest = right_child_index
 
       if smallest != index: