Merge pull request #301 from sesha3113/master

added singly linked list

Author: probot-auto-merge[bot]

singly linked list/singly limked list.c

@@ -0,0 +1,234 @@
+#include<stdio.h>
+#include<conio.h>
+#include<process.h>
+ 
+struct node
+{
+    int data;
+    struct node *next;
+}*start=NULL,*q,*t;
+ 
+int main()
+{
+    int ch;
+    void insert_beg();
+    void insert_end();
+    int insert_pos();
+    void display();
+    void delete_beg();
+    void delete_end();
+    int delete_pos();
+ 
+    while(1)
+    {
+        printf("\n\n---- Singly Linked List(SLL) Menu ----");
+        printf("\n1.Insert\n2.Display\n3.Delete\n4.Exit\n\n");
+        printf("Enter your choice(1-4):");
+        scanf("%d",&ch);
+ 
+        switch(ch)
+        {
+            case 1:
+                    printf("\n---- Insert Menu ----");
+                    printf("\n1.Insert at beginning\n2.Insert at end\n3.Insert at specified position\n4.Exit");
+                    printf("\n\nEnter your choice(1-4):");
+                    scanf("%d",&ch);
+ 
+                    switch(ch)
+                    {
+                        case 1: insert_beg();
+                                break;
+                        case 2: insert_end();
+                                break;
+                        case 3: insert_pos();
+                                break;
+                        case 4: exit(0);
+                        default: printf("Wrong Choice!!");
+                    }
+                    break;
+ 
+            case 2: display();
+                    break;
+ 
+            case 3: printf("\n---- Delete Menu ----");
+                    printf("\n1.Delete from beginning\n2.Delete from end\n3.Delete from specified position\n4.Exit");
+                    printf("\n\nEnter your choice(1-4):");
+                    scanf("%d",&ch);
+ 
+                    switch(ch)
+                    {
+                        case 1: delete_beg();
+                                break;
+                        case 2: delete_end();
+                                break;
+                        case 3: delete_pos();
+                                break;
+                        case 4: exit(0);
+                        default: printf("Wrong Choice!!");
+                    }
+                    break;
+            case 4: exit(0);
+                    default: printf("Wrong Choice!!");
+        }
+    }
+    return 0;
+}
+ 
+void insert_beg()
+{
+    int num;
+    t=(struct node*)malloc(sizeof(struct node));
+    printf("Enter data:");
+    scanf("%d",&num);
+    t->data=num;
+ 
+    if(start==NULL)        //If list is empty
+    {
+        t->next=NULL;
+        start=t;
+    }
+    else
+    {
+        t->next=start;
+        start=t;
+    }
+}
+ 
+void insert_end()
+{
+    int num;
+    t=(struct node*)malloc(sizeof(struct node));
+    printf("Enter data:");
+    scanf("%d",&num);
+    t->data=num;
+    t->next=NULL;
+ 
+    if(start==NULL)        //If list is empty
+    {
+        start=t;
+    }
+    else
+    {
+        q=start;
+        while(q->next!=NULL)
+        q=q->next;
+        q->next=t;
+    }
+}
+ 
+int insert_pos()
+{
+    int pos,i,num;
+    if(start==NULL)
+    {
+        printf("List is empty!!");
+        return 0;
+    }
+ 
+    t=(struct node*)malloc(sizeof(struct node));
+    printf("Enter data:");
+    scanf("%d",&num);
+    printf("Enter position to insert:");
+    scanf("%d",&pos);
+    t->data=num;
+ 
+    q=start;
+    for(i=1;i<pos-1;i++)
+    {
+        if(q->next==NULL)
+        {
+            printf("There are less elements!!");
+            return 0;
+        }
+ 
+        q=q->next;
+    }
+ 
+    t->next=q->next;
+    q->next=t;
+    return 0;
+}
+ 
+void display()
+{
+    if(start==NULL)
+    {
+        printf("List is empty!!");
+    }
+    else
+    {
+        q=start;
+        printf("The linked list is:\n");
+        while(q!=NULL)
+        {
+            printf("%d->",q->data);
+            q=q->next;
+        }
+    }
+}
+ 
+void delete_beg()
+{
+    if(start==NULL)
+    {
+        printf("The list is empty!!");
+    }
+    else
+    {
+        q=start;
+        start=start->next;
+        printf("Deleted element is %d",q->data);
+        free(q);
+    }
+}
+ 
+void delete_end()
+{
+    if(start==NULL)
+    {
+        printf("The list is empty!!");
+    }
+    else
+    {
+        q=start;
+        while(q->next->next!=NULL)
+        q=q->next;
+ 
+        t=q->next;
+        q->next=NULL;
+        printf("Deleted element is %d",t->data);
+        free(t);
+    }
+}
+ 
+int delete_pos()
+{
+    int pos,i;
+ 
+    if(start==NULL)
+    {
+        printf("List is empty!!");
+        return 0;
+    }
+ 
+    printf("Enter position to delete:");
+    scanf("%d",&pos);
+ 
+    q=start;
+    for(i=1;i<pos-1;i++)
+    {
+        if(q->next==NULL)
+        {
+            printf("There are less elements!!");
+            return 0;
+        }
+        q=q->next;
+    }
+ 
+    t=q->next;
+    q->next=t->next;
+    printf("Deleted element is %d",t->data);
+    free(t);
+ 
+    return 0;
+}