diff --git a/ex7/ex7.cpp b/ex7/ex7.cpp
new file mode 100644
index 0000000..2907e1c
--- /dev/null
+++ b/ex7/ex7.cpp
@@ -0,0 +1,8 @@
+#include <stdio.h>
+#include "stack.h"
+
+int main()
+{
+    printf("g")
+    
+}
\ No newline at end of file
diff --git a/ex7/stack.cpp b/ex7/stack.cpp
new file mode 100644
index 0000000..9b642c5
--- /dev/null
+++ b/ex7/stack.cpp
@@ -0,0 +1,27 @@
+#include "stack.h"
+
+// template <class T>
+// void Stack<T>::push (T const& elem) 
+// { 
+//     _elems.add(elem);    
+// } 
+ 
+// template <class T>
+// T Stack<T>::pop () 
+// { 
+//     if (_elems.getused()) { 
+//         return NULL;
+//     }
+//     // 删除最后一个元素
+//     return _elems.remove_back() 
+// } 
+ 
+// template <class T>
+// T Stack<T>::top () const 
+// { 
+//     if (_elems.getused()) { 
+//        return NULL;
+//     }
+//     // 返回最后一个元素的副本 
+//     return _elems[_elems.getused()-1];      
+// } 
\ No newline at end of file
diff --git a/ex7/stack.h b/ex7/stack.h
new file mode 100644
index 0000000..710cb66
--- /dev/null
+++ b/ex7/stack.h
@@ -0,0 +1,42 @@
+template <class T>
+class Stack { 
+  private: 
+    T _v[10];
+    int _len=10;
+    int used=0; 
+  public: 
+    void push(T const&); 
+    T pop();              
+    T top() const;         
+    bool empty() const;
+
+  protected:
+//    void expand()
+// {
+
+//     _len = _len * 2;
+//     T *p = new T[_len];
+
+//     for (int i = 0; i <= _used; i++)
+//         p[i] = _v[i];
+
+//     delete[] _v;
+//     _v = p;
+// }
+
+// template <class T>
+// void Vec<T>::shrink()
+// {
+//     if (((double)_used / (double)_len) >= 0.25)
+//         return;
+
+//     _len = _len >> 1;
+//     T *p = new T[_len];
+
+//     for (int i = 0; i <= _used; i++)
+//         p[i] = _v[i];
+
+//     delete[] _v;
+//     _v = p;
+// }
+}; 
\ No newline at end of file