Merge pull request #540 from Mayuri-cell/master

Stack Data Structure

Author: Saviour1001

Data Structures/Stacks/stack.c

@@ -0,0 +1,187 @@
+/*
+    Title : Stack Operations :
+            1.PUSH    2.POP   3.DISPLAY   4.PEAK ELEMENT
+            are performed using arrays . i.e Static memory allocation in c language .
+            User need to choose the option number which user  wants to perform .
+            PUSH : To enter the data elements .
+            POP  : To POP Out the element (To delete).
+            Peak : To get the top most element present on the stack.
+            It follows first in last out principle .
+            Node can be entered and can be deleted from one end only.
+*/
+#include<stdio.h>
+#include<stdlib.h>
+void main()
+{
+   int size,opt,i,x;
+   printf(" \n *******  WELCOME  ******* : \n We are going to implement stack data structure : \n It follows LIFO  (Last In First Out Principle .)\n");
+   printf("\n Enter the size of STACK : \n");
+   scanf("%d",&size);
+   int top=-1;
+   int arr[size];
+
+   do
+   {    printf("\n ---- 1.PUSH ---- \n ---- 2.DISPLAY ---- \n ---- 3.POP ---- \n ---- 4.Peak ---- \n ---- 5.Exit ---- ");
+        printf("\n Enter the option number : \n");
+        scanf("%d",&opt);
+         switch(opt)
+         {
+           case 1 : printf("\n       PUSH         ");
+                    if(top==size-1)
+                    { printf("\n STACK IS FULL ! \n");  }
+                    else
+                    {  top++;
+                       printf("\n ENETR PUSH THE ELEMENT \n");
+                       scanf("%d",&x);
+                       arr[top]=x;  }
+                       break;
+           case 2 : printf("\n          DISPLAY          ");
+                    if(top<=-1)
+                    { printf("\n The Stack is Empty ! ");
+                       top=-1; }
+                      else
+                   {  printf("\n The elements are : " );
+                      for(i=top;i>=0;i--)
+                      {  printf("\n %d   " , arr[i] ); } }
+                      break;
+          case 3:   printf("\n           POP             ");
+
+                  if(top<=-1){ printf("\n The Stack is Empty ! \n ");
+                               top=-1; }
+                  else {
+                        printf("\n Element popped out is : %d " ,arr[top]);
+                        top--;
+                        if(top<-1) { top=-1 ; }
+                      }
+                  break;
+
+          case 4 :   printf("\n           Peak           ");
+                     if(top<=-1)
+                      { printf("\n No element is at the top of the stack . \n Empty stack !");
+                        top=-1; }
+
+                     else
+                      { printf("\n The present top/peak element of the stack : %d ",arr[top]); }
+                      break ;
+          case 5 :
+                    exit(0);
+                    break ;
+          default : printf("\n Invalid Option !!\n Please try again . ");
+                    break;
+
+         }
+    printf("\n DO YOU WISH TO CONTINUE ? \n 1.Yes \n 2.No\n");  /* Enter 1 or other tahn 0 to continue otherwise enter 2 .  */
+    scanf("%d",&opt);
+
+   }
+   while(opt!=2);
+}
+/*
+Enter the size of STACK :
+2
+
+---- 1.PUSH ----
+---- 2.DISPLAY ----
+---- 3.POP ----
+---- 4.Peak ----
+---- 5.Exit ----
+Enter the option number :
+1
+
+      PUSH
+ENETR PUSH THE ELEMENT
+1
+
+DO YOU WISH TO CONTINUE ?
+1.Yes
+2.No
+1
+
+---- 1.PUSH ----
+---- 2.DISPLAY ----
+---- 3.POP ----
+---- 4.Peak ----
+---- 5.Exit ----
+Enter the option number :
+1
+
+      PUSH
+ENETR PUSH THE ELEMENT
+2
+
+DO YOU WISH TO CONTINUE ?
+1.Yes
+2.No
+1
+
+---- 1.PUSH ----
+---- 2.DISPLAY ----
+---- 3.POP ----
+---- 4.Peak ----
+---- 5.Exit ----
+Enter the option number :
+1
+
+      PUSH
+STACK IS FULL !
+
+DO YOU WISH TO CONTINUE ?
+1.Yes
+2.No
+1
+
+---- 1.PUSH ----
+---- 2.DISPLAY ----
+---- 3.POP ----
+---- 4.Peak ----
+---- 5.Exit ----
+Enter the option number :
+2
+
+         DISPLAY
+The elements are :
+2
+1
+DO YOU WISH TO CONTINUE ?
+1.Yes
+2.No
+1
+
+---- 1.PUSH ----
+---- 2.DISPLAY ----
+---- 3.POP ----
+---- 4.Peak ----
+---- 5.Exit ----
+Enter the option number :
+3
+
+          POP
+Element popped out is : 2
+DO YOU WISH TO CONTINUE ?
+1.Yes
+2.No
+1
+
+---- 1.PUSH ----
+---- 2.DISPLAY ----
+---- 3.POP ----
+---- 4.Peak ----
+---- 5.Exit ----
+Enter the option number :
+4
+
+          Peak
+The present top/peak element of the stack : 1
+DO YOU WISH TO CONTINUE ?
+1.Yes
+2.No
+1
+
+---- 1.PUSH ----
+---- 2.DISPLAY ----
+---- 3.POP ----
+---- 4.Peak ----
+---- 5.Exit ----
+Enter the option number :
+5
+*/