Adding 3rd assignment, stacks and queues

Stacks&Queues/TStack.cpp

@@ -0,0 +1,43 @@
+#include "TStack.h"
+#include <iostream>
+
+// Time complexity O(1) - always append to the end of the array and use that as the top of the stack
+// Space complexity O(1) - no need to save helper variables, just place on top of existing, size-static stack
+void TStack::Push(const int item)
+{
+    if (top >= MAX_SIZE)
+        throw std::overflow_error("Stack overflow");
+    stack[top++] = item;
+}
+
+
+// Time and space complexity both O(1) - Only works with the top element so if you have
+// 5 or 500 elements in the stack the result will be the same
+// Only returns and removes top element
+int TStack::Pop()
+{
+    if (top == 0)
+        throw std::underflow_error("Stack underflow");
+    return stack[--top];
+}
+
+// Time and space complexity O(1) - only returns the top element
+int TStack::Peek() const
+{
+    if (top == 0)
+        throw std::underflow_error("Stack underflow");
+    return stack[top - 1];
+}
+
+// O(1) for both, checks to see if the stack is empty or not
+// doesn't determine exact amount - just makes sure it has one
+bool TStack::IsEmpty() const
+{
+    return top == 0;
+}
+
+
+
+
+
+