Do a better RandomizedSet

leetcode/stuff.py

@@ -396,7 +396,7 @@ def h_index(citations: list[int]) -> int:
     return last_qualified or 0
 
 
-class RandomizedSet:
+class SlowRandomizedSet:
     def __init__(self):
         self._i: set[int] = set()
 
@@ -412,4 +412,36 @@ class RandomizedSet:
         return False
 
     def getRandom(self) -> int:
-        return next(iter(sorted(list(self._i), key=lambda _: random.random())))
+        return random.choice(list(self._i))
+
+
+class RandomizedSet:
+    def __init__(self):
+        self._l: list[int] = []
+        self._m: dict[int, int] = {}
+
+    def insert(self, val: int) -> bool:
+        if val in self._m:
+            return False
+
+        self._m[val] = len(self._l)
+        self._l.append(val)
+
+        return True
+
+    def remove(self, val: int) -> bool:
+        if val not in self._m:
+            return False
+
+        val_loc = self._m[val]
+        last_val = self._l[-1]
+        self._l[val_loc] = last_val
+        self._m[last_val] = val_loc
+
+        self._l.pop()
+        self._m.pop(val)
+
+        return True
+
+    def getRandom(self) -> int:
+        return random.choice(self._l)