A poorly-made min stack

leetcode/stuff.py

@@ -138,3 +138,27 @@ class Roman:
             total += cls.ALL[c]
 
         return total
+
+
+class MinStack:
+    def __init__(self):
+        self._v: list[int] = []
+        self._min: int | None = None
+
+    def push(self, val: int) -> None:
+        self._v.append(val)
+
+        if self._min is None or self._min > val:
+            self._min = val
+
+    def pop(self) -> None:
+        popped = self._v.pop(-1)
+
+        if popped == self._min:
+            self._min = min(self._v)
+
+    def top(self) -> int:
+        return self._v[-1]
+
+    def getMin(self) -> int:  # no qa
+        return typing.cast(int, self._min)