feat: implement least interval

Author: bujosa

alternative/medium/task_scheduler.py

@@ -0,0 +1,26 @@
+from typing import List
+import heapq
+from collections import deque, Counter
+
+def leastInterval(tasks: List[str], n: int) -> int:
+    maxHeap = []
+    time = 0
+    letter_count = {}
+    q = deque()
+
+    letter_count = Counter(tasks)
+    for value in letter_count.values():
+        heapq.heappush(maxHeap, -value)
+    
+    while maxHeap or q:
+        time+=1
+        if maxHeap:
+            cnt = -heapq.heappop(maxHeap) - 1
+            if cnt > 0:
+                q.append([-cnt, time + n])
+        if q and q[0][1] == time:
+            heapq.heappush(maxHeap, q.popleft()[0])
+    return time
+
+print(leastInterval(["A","A","A","B","B","B"], 2))
+assert leastInterval(["A","A","A","B","B","B"], 2) == 8