first working threaded implementation of adt_checking

Assignment_3/lib/SimpleLockingStack.h

@@ -0,0 +1,16 @@
+
+#include <vector>
+#include <mutex>
+
+#include "Stack.h"
+
+class SimpleLockingStack:public Stack{
+    private:
+        std::vector<int> vec;
+        std::mutex mut;
+    public:
+        SimpleLockingStack(ADTOperationQueue * queue);
+        void push(int element);
+        int pop();
+        int size();
+};