feat: solve new question

Author: arwildo

min-stack/main.ts

@@ -0,0 +1,45 @@
+class MinStack {
+    stack: number[];
+    minStack: number[];
+
+    constructor() {
+        this.stack = [];
+        this.minStack = [];
+    }
+
+    push(val: number): void {
+       this.stack.push(val); 
+
+       if (this.minStack.length === 0 || this.minStack[this.minStack.length - 1] >= val){
+            this.minStack.push(val);
+       }
+    }
+
+    pop(): void {
+       const popVal = this.stack.pop(); 
+
+       if (popVal === this.minStack[this.minStack.length - 1]) {
+            this.minStack.pop();
+       }
+    }
+
+    top(): number {
+       return this.stack[this.stack.length - 1];
+    }
+
+    getMin(): number {
+        return this.minStack[this.minStack.length - 1];
+    }
+}
+
+/**
+this.stack = 2, 0, 3
+this.minStack = 2, 0
+
+ * Your MinStack object will be instantiated and called as such:
+ * var obj = new MinStack()
+ * obj.push(val)
+ * obj.pop()
+ * var param_3 = obj.top()
+ * var param_4 = obj.getMin()
+ */