diff --git a/assignment6 (1).c b/assignment6 (1).c
new file mode 100644
index 0000000..b4df7f3
--- /dev/null
+++ b/assignment6 (1).c	
@@ -0,0 +1,112 @@
+#include<stdio.h>
+#define MAX 50
+struct queue{
+char id[50]
+}q[50];
+
+int h=-1,t=-1;
+void enqueue();
+void dequeue();
+void display();
+main()
+{
+
+	int choice;
+	char ans='y';
+	printf("1) Airplane lands.\n");
+	printf("2) Airplane takes off\n");
+	printf("3) Display\n");
+	printf("4) Exit\n\n");
+	while(ans!='n'&&ans!='N')
+	{
+
+		printf("Enter the choice:");
+		scanf("%d",&choice);
+		switch(choice)
+		{
+			case 1:
+				enqueue();
+				break;
+			case 2:
+				dequeue();
+				break;
+			case 3:
+				display();
+				break;
+			case 4:
+				return;
+			default:
+				printf("Enter the valid choice.");
+				break;
+		}
+		printf("\nDo you want to continue.? ");
+		scanf("%c",&ans);
+		scanf("%c",&ans);
+	}
+}
+
+
+
+void enqueue()
+{
+	if(t==MAX-1)
+	t=0;
+	else
+	t+=1;
+	if(h==t)
+	{
+		printf("Airport is full");
+		return;
+	}
+	printf("\nEnter the ID of plane:");
+	scanf("%s",q[t].id);
+	if(h==-1)
+	h=0;
+
+}
+
+
+void dequeue()
+{
+	if(t==-1)
+	{		
+		printf("\nNo such plan in Airport which can do take off.\n");
+		return;
+	}
+	else
+	{
+		printf("The plan with ID %s departured.",q[h].id);
+	}
+	if(h==t)
+	{
+		h=-1;
+		t=-1;
+		return;
+	}
+	else if(h==MAX-1)
+	h=0;
+	else
+	h+=1;
+}	
+
+
+void display()
+{
+   	int i;
+	if(h==-1)
+	printf("Airport is Empty.");
+	else
+	{	
+		for(i=h;i!=t+1;i++)
+		{
+			printf("%s\n",q[i].id);
+			if(i==MAX-1)
+			i=-1;
+		}
+	}
+}
+
+
+
+
+
diff --git a/lnklist.c b/lnklist.c
new file mode 100644
index 0000000..a157fc2
--- /dev/null
+++ b/lnklist.c
@@ -0,0 +1,424 @@
+#include<stdio.h>
+#include<stdlib.h>
+
+struct node{
+char name[20];
+int rollno;
+float cgpa;
+struct node* link;
+};
+struct node* newnode;
+void display(struct node* head)
+{
+	if(head==NULL)
+	{
+	printf("The linked list is empty!!\n");
+	}
+
+	else
+	{
+	struct node* newnode;
+	newnode=head;
+	int count=1;
+		while(newnode!=NULL)
+		{
+		printf("%d\n",count);
+		printf("%s\n",newnode->name);
+		printf("%d\n",newnode->rollno);
+		printf("%f\n\n",newnode->cgpa);
+		newnode=newnode->link;
+		count=count+1;
+		}
+	}
+
+}
+
+void searchrollnno(struct node* head , int r)
+{
+if(head==NULL)
+	{
+	printf("The linked list is empty\n");
+	}
+
+	else
+	{
+	struct node* newnode;
+	newnode=head;
+
+		while(newnode->rollno!=r && newnode!=NULL)
+		{
+		newnode=newnode->link;
+		}
+		if(newnode!=NULL)
+		{
+		printf("The Record is = >>\n");
+		printf("%s\n",newnode->name);
+		printf("%d\n",newnode->rollno);
+		printf("%f\n\n",newnode->cgpa);
+		}
+		else
+		printf("Node not found\n");
+	}
+
+}
+
+
+void searchname(struct node* head, char* s)
+{
+if(head==NULL)
+{
+printf("The record not found\n");
+}
+
+else if(head->link==NULL)
+{
+int i,co=0;
+	for(i=0;s[i]!='\0';i++)
+	{
+		if(head->name[i]!=s[i])
+		{
+		printf("The Record is not found\n");
+		co=1;
+		break;
+		}
+
+	}
+if(co==0)
+printf("Record found at node number 1\n");
+
+}
+
+else
+{
+newnode=head;
+int no=0;
+while(newnode!=NULL)
+{
+int i,co=0;
+	for(i=0;s[i]!='\0';i++)
+	{
+		if(newnode->name[i]!=s[i])
+		{
+		co=1;
+		break;
+		}
+
+	}
+if(co==1)
+{
+newnode=newnode->link;
+no++;
+}
+else
+{
+printf("Record at node number %d \n",no+1);
+break;
+}
+}
+
+}
+
+}
+
+void searchcgpa(struct node* head,float p){
+if(head==NULL)
+{
+printf("The record not found\n");
+}
+
+else if(head->link==NULL)
+{
+	if(head->cgpa!=p)
+	{
+	printf("The record not found\n");
+	}
+	else
+	printf("Record at node number 1\n");
+
+}
+
+else{
+int co=0,no=0;
+newnode=head;
+while(newnode!=NULL)
+{
+	if(newnode->cgpa==p)
+	{
+	printf("Record at node number %d \n",no+1);
+	co++;
+	break;
+	}
+	else
+	{
+	newnode=newnode->link;
+	no++;
+	}
+}
+if(co==0)
+printf("record not found\n");
+
+}
+}
+
+struct node* insertatend(struct node* head)
+{
+
+struct node* new=(struct node* )malloc(sizeof(struct node));
+printf("Enter the name of the student:- ");
+scanf("%s",new->name);
+printf("Enter the roll no. of the student:-");
+scanf("%d",&(new->rollno));
+printf("Enter the cgpa of the student:-");
+scanf("%f",&(new->cgpa));
+
+new->link=NULL;
+if(head==NULL)
+{
+	head=new;
+}
+
+else
+{
+	struct node* newnode;
+	newnode=head;
+	while(newnode->link!=NULL)
+	{
+	newnode=newnode->link;
+	}
+	newnode->link=new;
+}
+return head;
+}
+
+
+struct node* insertatfront(struct node* head)
+{
+struct node* new=(struct node* )malloc(sizeof(struct node));
+printf("Enter the name of the student:- ");
+scanf("%s",(new->name));
+printf("Enter the roll no. of the student:-");
+scanf("%d",&(new->rollno));
+printf("Enter the cgpa of the student:-");
+scanf("%f",&(new->cgpa));
+new->link=NULL;
+
+	if(head==NULL)
+	{
+	head=new;
+	}
+
+	else
+	{
+	new->link=head;
+	head=new;
+
+	}
+return head;
+}
+
+struct node* insertinbetween(struct node* head)
+{
+int count=0,c;
+struct node* new=(struct node* )malloc(sizeof(struct node));
+printf("Enter the name of the student:- ");
+scanf("%s",(new->name));
+printf("Enter the roll no. of the student:-");
+scanf("%d",&(new->rollno));
+printf("Enter the cgpa of the student:-");
+scanf("%f",&(new->cgpa));
+new->link=NULL;
+struct node* newnode;
+struct node* newnode1;
+printf("Enter the node where you want to add a new node:- ");
+scanf("%d",&c);
+	if(head==NULL)
+	{
+	printf("The linked list is empty");
+	}
+
+	else
+	{
+	newnode=head;
+	count=1;
+	while(count!=c && newnode!=NULL)
+	{
+	newnode=newnode->link;
+	count++;
+	}
+	if(newnode==NULL)
+	printf("Node not found");
+	else
+	{
+	newnode1=newnode->link;
+	newnode->link=new;
+	new->link=newnode1;
+
+	}
+	}
+return head;
+}
+
+
+
+struct node* deleteatfront(struct node* head)
+{
+	if(head==NULL)
+	{
+	printf("the linked list is empty\n");
+
+	}
+
+	else if(head->link==NULL)
+	{
+	head=NULL;
+	}
+
+	else
+	{
+	struct node* newnode;
+	newnode=head->link;
+	head=newnode;
+	}
+return head;
+}
+
+struct node* deleteinbetween(struct node* head , int pos)
+{
+if(head==NULL)
+printf("The linked list is empty!!\n");
+
+else if(pos==1 && head->link==NULL)
+{
+return NULL;
+}
+else
+{
+if(pos==1)
+{
+	return head->link;
+}
+else
+{
+	newnode=head;
+	int count=1;
+	while(count+1!=pos)
+	{
+	newnode=newnode->link;
+	count++;
+	}
+
+	newnode->link=(newnode->link)->link;
+}
+}
+return head;
+}
+
+struct node* deleteatend(struct node* head)
+{
+	if(head==NULL)
+	{
+	printf("the linked list is empty\n");
+	}
+
+	else if(head->link==NULL)
+	{
+	head=NULL;
+	}
+
+	else
+	{
+	struct node* newnode;
+	newnode=head;
+	while((newnode->link)->link!=NULL)
+	{
+	newnode=newnode->link;
+	}
+	newnode->link=NULL;
+	}
+return head;
+}
+
+
+void main()
+{
+struct node* head=NULL;
+int ch,y=1,r;
+float cg;
+char s1[20];
+do
+{
+printf("1.Insert in the front \n");
+printf("2.Insert at the end \n");
+printf("3.Insert between nodes \n");
+printf("4.Delete an element from the front \n");
+printf("5.Delete an element from the end \n");
+printf("6.Delete an element from inbetween node.\n");
+printf("7.Display the linked list\n");
+
+
+printf("8.Search for a record by Rollno.\n");
+printf("9.Search for a record by Name.\n");
+printf("10.Search for a record by CGPA.\n");
+
+
+printf("Enter your choice : -");
+scanf("%d",&ch);
+switch(ch)
+{
+	case 1:
+	head=insertatfront(head);
+	break;
+
+	case 2:
+	head=insertatend(head);
+	break;
+
+	case 3:
+	head=insertinbetween(head);
+	break;
+
+	case 4:
+	head=deleteatfront(head);
+	break;
+
+	case 5:
+	head=deleteatend(head);
+	break;
+
+	case 7:
+	display(head);
+	break;
+
+	case 8:
+	printf("enter the roll no. you want the search:-");
+	scanf("%d",&r);
+	searchrollnno(head,r);
+	break;
+
+	case 6:
+	printf("please enter the position of the node you want to delete:-");
+	scanf("%d",&r);
+	head=deleteinbetween(head,r);
+	break;
+
+	case 9:
+	printf("enter the Name you want the search:-");
+	scanf("%s",&s1);
+	searchname(head,s1);
+	break;
+
+	case 10:
+	printf("enter the CGPA you want the search:-");
+	scanf("%f",&cg);
+	searchcgpa(head,cg);
+	break;
+  case 11:
+	break;
+	default:
+	printf("wrong choice\n");
+}
+}while(ch!=11);
+
+
+return 0;
+}