Stack using linked list.c

C/Stack using linked list.c

@@ -0,0 +1,157 @@
+#include <stdio.h>
+#include <stdlib.h>
+struct node
+{
+int info;
+struct node *ptr;
+}*top,*top1,*temp;
+int topelement();
+void push(int data);
+void pop();
+void empty();
+void display();
+void destroy();
+void stack_count();
+void create();
+int count = 0;
+void main()
+{
+int no, ch, e;
+printf("\n 1 - Push");
+printf("\n 2 - Pop");
+printf("\n 3 - Top");
+printf("\n 4 - Empty");
+printf("\n 5 - Exit");
+printf("\n 6 - Dipslay");
+printf("\n 7 - Stack Count");
+printf("\n 8 - Destroy stack");
+create();
+while (1)
+{
+printf("\n Enter choice : ");
+scanf("%d", &ch);
+switch (ch)
+{
+case 1:
+printf("Enter data : ");
+scanf("%d", &no);
+push(no);
+break;
+case 2:
+pop();
+break;
+case 3:
+if (top == NULL)
+printf("No elements in stack");
+else
+{
+e = topelement();
+printf("\n Top element : %d", e);}
+break;
+case 4:
+empty();
+break;
+case 5:
+exit(0);
+case 6:
+display();
+break;
+case 7:
+stack_count();
+break;
+case 8:
+destroy();
+break;
+default :
+printf(" Wrong choice, Please enter correct choice ");
+break;
+}
+}
+}
+/* Create empty stack */
+void create()
+{
+top = NULL;
+}
+/* Count stack elements */
+void stack_count()
+{
+printf("\n No. of elements in stack : %d", count);
+}
+/* Push data into stack */
+void push(int data)
+{
+if (top == NULL)
+{
+top =(struct node *)malloc(1*sizeof(struct node));
+top->ptr = NULL;
+top->info = data;
+}
+else
+{
+temp =(struct node *)malloc(1*sizeof(struct node));
+temp->ptr = top;
+temp->info = data;
+top = temp;
+}
+count++;
+}
+/* Display stack elements */
+void display()
+{
+top1 = top;
+if (top1 == NULL)
+{
+printf("Stack is empty");
+return;}
+while (top1 != NULL)
+{
+printf("%d ", top1->info);
+top1 = top1->ptr;
+}
+}
+/* Pop Operation on stack */
+void pop()
+{
+top1 = top;
+if (top1 == NULL)
+{
+printf("\n Error : Trying to pop from empty stack");
+return;
+}
+else
+top1 = top1->ptr;
+printf("\n Popped value : %d", top->info);
+free(top);
+top = top1;
+count--;
+}
+/* Return top element */
+int topelement()
+{
+return(top->info);
+}
+/* Check if stack is empty or not */
+void empty()
+{
+if (top == NULL)
+printf("\n Stack is empty");
+else
+printf("\n Stack is not empty with %d elements", count);
+}
+/* Destroy entire stack */
+void destroy()
+{
+top1 = top;
+while (top1 != NULL)
+{
+top1 = top->ptr;
+free(top);
+top = top1;
+top1 = top1->ptr;
+}
+free(top1);
+top = NULL;
+printf("\n All stack elements destroyed");
+count = 0;
+}