Add solution for arrays: Mininum stack

neetcode/arrays/mininum_stack/solution.py

@@ -0,0 +1,35 @@
+class MinStack:
+    def __init__(self):
+        self.stack = []
+        self.min_stack = []
+
+    def push(self, val: int) -> None:
+        self.stack.append(val)
+        if not self.min_stack:
+            self.min_stack.append(val)
+        else:
+            self.min_stack.append(min(val, self.min_stack[-1]))
+
+    def pop(self) -> None:
+        if self.min_stack:
+            self.min_stack.pop()
+        if self.stack:
+            self.stack.pop()
+        else:
+            return None
+
+    def top(self) -> int:
+        return self.stack[-1]
+
+    def getMin(self) -> int:
+        if self.min_stack:
+            return self.min_stack[-1]
+        else:
+            return None
+
+if __name__ == "__main__":
+    s = MinStack()
+    s.push(12)
+    s.pop()
+    s.pop()
+    print(s.getMin())