Added program of Stack using linked list

PratikPrakhar · web-flow · commit 9cecedcc084b · 2021-10-19T19:06:29.000+05:30
diff --git a/Stack using linked list.c b/Stack using linked list.c
@@ -0,0 +1,106 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+struct Node
+{
+    int data;
+    struct Node *next;
+};
+
+struct Node *head = NULL;
+
+void push(int value)
+{
+    struct Node *n = (struct Node *)malloc(sizeof(struct Node *));
+    if (head == NULL)
+    {
+        head = n;
+        n->data = value;
+        n->next = NULL;
+        return;
+    }
+
+    n->next = head;
+    n->data = value;
+    head = n;
+}
+
+void pop()
+{
+    struct Node *temp = head;
+    if (head == NULL)
+    {
+        printf("\nStack is empty.\n");
+        return;
+    }
+
+    head = head->next;
+    temp->next = NULL;
+}
+
+void peek()
+{
+    if (head == NULL)
+    {
+        printf("\nStack is empty.\n");
+        return;
+    }
+
+    printf("The top element is: %d\n", head->data);
+}
+
+void display()
+{
+    struct Node *temp = head;
+    if (head == NULL)
+    {
+        printf("\nStack is empty.\n");
+        return;
+    }
+    printf("\nElements of stack are:\n");
+    while (temp != NULL)
+    {
+        printf("%d\n", temp->data);
+        temp = temp->next;
+    }
+}
+
+int main()
+{
+    while (1)
+    {
+        printf("\n=======Menu=======\n");
+        printf("1. Push\n");
+        printf("2. Pop\n");
+        printf("3. Peek\n");
+        printf("4. Display\n");
+        printf("5. Exit\n\n");
+        int c, n;
+        scanf("%d", &c);
+        switch (c)
+        {
+        case 1:
+            printf("Enter the element to be inserted: ");
+            scanf("%d", &n);
+            push(n);
+            break;
+        case 2:
+            pop();
+            break;
+        case 3:
+            peek();
+            break;
+        case 4:
+            display();
+            break;
+        case 5:
+            exit(0);
+            break;
+
+        default:
+            printf("Please select a valid option.");
+        }
+    }
+
+    return 0;
+}
