Merge pull request #179 from itsAshna/patch-2

LinkedStack.cpp

Author: larissalages

data_structures/Cpp/Stack/LinkedStack.cpp

@@ -0,0 +1,144 @@
+#include <bits/stdc++.h>  
+using namespace std;  
+  
+struct Node  
+{  
+    int data;  
+    struct Node* link;  
+};  
+  
+struct Node* top;  
+  
+// Utility function to add an element  
+// data in the stack insert at the beginning  
+void push(int data)  
+{  
+      
+    // Create new node temp and allocate memory  
+    struct Node* temp;  
+    temp = new Node();  
+  
+    // Check if stack (heap) is full.  
+    // Then inserting an element would  
+    // lead to stack overflow  
+    if (!temp) 
+    {  
+        cout << "\nHeap Overflow";  
+        exit(1);  
+    }  
+  
+    // Initialize data into temp data field  
+    temp->data = data;  
+  
+    // Put top pointer reference into temp link  
+    temp->link = top;  
+  
+    // Make temp as top of Stack  
+    top = temp;  
+}  
+  
+// Utility function to check if  
+// the stack is empty or not  
+int isEmpty()  
+{  
+    return top == NULL;  
+}  
+  
+// Utility function to return top element in a stack  
+int peek()  
+{  
+      
+    // Check for empty stack  
+    if (!isEmpty())  
+        return top->data;  
+    else
+        exit(1);  
+}  
+  
+// Utility function to pop top  
+// element from the stack  
+void pop()  
+{  
+    struct Node* temp;  
+  
+    // Check for stack underflow  
+    if (top == NULL)  
+    {  
+        cout << "\nStack Underflow" << endl;  
+        exit(1);  
+    }  
+    else
+    {  
+          
+        // Top assign into temp  
+        temp = top;  
+  
+        // Assign second node to top  
+        top = top->link;  
+  
+        // Destroy connection between 
+        // first and second  
+        temp->link = NULL;  
+  
+        // Release memory of top node  
+        free(temp);  
+    }  
+}  
+  
+// Function to print all the  
+// elements of the stack  
+void display()  
+{  
+    struct Node* temp;  
+  
+    // Check for stack underflow  
+    if (top == NULL) 
+    {  
+        cout << "\nStack Underflow";  
+        exit(1);  
+    }  
+    else 
+    {  
+        temp = top;  
+        while (temp != NULL) 
+        {  
+  
+            // Print node data  
+            cout << temp->data << "-> ";  
+  
+            // Assign temp link to temp  
+            temp = temp->link;  
+        }  
+    }  
+}  
+  
+// Driver Code  
+int main()  
+{  
+      
+    // Push the elements of stack  
+    push(11);  
+    push(22);  
+    push(33);  
+    push(44);  
+  
+    // Display stack elements  
+    display();  
+  
+    // Print top element of stack  
+    cout << "\nTop element is "
+         << peek() << endl;  
+  
+    // Delete top elements of stack  
+    pop();  
+    pop();  
+  
+    // Display stack elements  
+    display();  
+  
+    // Print top element of stack  
+    cout << "\nTop element is " 
+         << peek() << endl;  
+           
+    return 0;  
+}