Added code for Stack implementation using Queue

Stack/stack_implementation_using_queue.cpp

@@ -0,0 +1,79 @@
+#include<bits/stdc++.h>
+using namespace std;
+class Stack
+{
+    int Size;
+    queue<int> q1;
+    queue<int> q2;
+
+public:
+    Stack()
+    {
+        Size = 0;
+    }
+    void push(int value)
+    {
+        q2.push(value);
+        Size++;
+        while (!q1.empty())
+        {
+            q2.push(q1.front());
+            q1.pop();
+        }
+        queue<int> temp = q1;
+        q1 = q2;
+        q2 = temp;
+    }
+    void pop()
+    {
+        q1.pop();
+        Size--;
+    }
+    bool empty()
+    {
+        if (q1.empty())
+        {
+            return true;
+        }
+        return false;
+    }
+    int top()
+    {
+        if (!empty())
+        {
+            return q1.front();
+        }
+        return -1;
+    }
+    int size()
+    {
+        return Size;
+    }
+};
+
+int main()
+{
+    Stack st;
+    st.push(4);
+    st.push(3);
+    st.push(2);
+    st.push(1);
+    cout<<"Top Element : " << st.top() << endl;
+    cout <<"Size : "<< st.size() << endl;
+    cout<<"-----After 1st Pop-----"<<endl;
+    st.pop();
+    cout<<"Top Element : " << st.top() << endl;
+    cout <<"Size : "<< st.size() << endl;
+    cout<<"-----After 2nd Pop-----"<<endl;
+    st.pop();
+    cout<<"Top Element : " << st.top() << endl;
+    cout <<"Size : "<< st.size() << endl;
+    cout<<"-----After 3rd Pop-----"<<endl;
+    st.pop();
+    cout<<"Top Element : " << st.top() << endl;
+    cout <<"Size : "<< st.size() << endl;
+    cout<<"-----After 4th Pop-----"<<endl;
+    st.pop();
+    cout<<"Top Element : " << st.top() << endl;
+    cout <<"Size : "<< st.size() << endl;
+}