Mim's doubly link list

#include<stdio.h>
#include<stdlib.h>

typedef struct node
{
    int a;
    struct node*next,*prev;
} node;


node*head=NULL,*tail=NULL;

int main()
{
    int choice;
    while(1)
    {
        printf("\t\t\t\t\n\nDoubly linked list\n\n");


        printf("\t\t\t\t\n1. Add First\n");
        printf("\t\t\t\t\n2. Add Any\n");
        printf("\t\t\t\t\n3. Delete Elements\n");
        printf("\t\t\t\t\n4. Display\n");
        printf("\t\t\t\t\n5. Delete Position\n");
        printf("\t\t\t\t\n6. Search Data\n");
        printf("\t\t\t\t\n7. Add end\n\n");

        printf("Enter your choice:");

        scanf("%d",&choice);

        switch(choice)
        {
        case 1 :
            Add_first();
            break;
        case 2:
            Add_any();
            break;
        case 3 :
            delete_data();
            break;
        case 4:
            display_first();
            break;
        case 5:
            Delete_Position();
            break;
        case 6:
            Search_Data();
            break;
        case 7:
            Add_End();
            break;

           dafault:
            printf("Invalid choice");

        }
    }
return 0;}

void Add_first()
{
    node *N=(node*)malloc(sizeof(node));
    printf("Enter the number:");
    scanf(" %d",&N->a);
    N->next=NULL;
    N->prev=NULL;
    if(head==NULL)
    {
        head=N;
        tail=N;
    }
    else
    {
        head->prev=N;
        N->next=head;
        head=N;

    }
}
void Add_any()
{
    int m;
    node *list=head;
    node *N=(node*)malloc(sizeof(node));
    printf("Enter the number:");
    scanf(" %d",&N->a);
    N->next=NULL;
    N->prev=NULL;
    printf("Enter Position: ");
    scanf(" %d",&m);
    if(m==1 )
    {
        if(head==NULL)
        {
            head=N;
            tail=N;
        }
        else
        {
            head->prev=N;
            N->next=head;
            head=N;
        }
    }
    else
    {
        m=m-2;
        while(m!=0 && list->next!=NULL)
        {
            list=list->next;
            m--;
        }
        if(list->next==NULL)
        {
            N->prev=tail;
            tail->next=N;
            tail=N;

        }
        else
        {
            list->next->prev=N;
            N->next=list->next;
            N->prev=list;
            list->next=N;
        }
    }


}
void Add_End()
{
    node *N=(node*)malloc(sizeof(node));
    printf("enter the number:");
    scanf(" %d",&N->a);
    N->next=NULL;
    N->prev=NULL;
    node *list=head;
    if(head==NULL)
    {
        head=N;
        tail=N;
    }
    else
    {
        tail->next=N;
        N->prev=tail;
        tail=N;
    }

}



void  delete_data()
{
    int d;
    printf("Enter the number:");
    scanf(" %d",&d);
    node*list=head;
    if(head==NULL)
    {
        printf("No Data!!\n\n");
    }
    else if(list->a==d)
    {
        if(list->next==NULL)
        {
            head=NULL;
            tail=NULL;
            printf("Data Deleted\n\n");
            free(list);
        }
        else
        {
            list->next->prev=NULL;
            head=list->next;
            printf("Data Deleted\n\n");
            free(list);
        }
    }
    else
    {
        node*temp;
        while(list->a!=d && list->next!=NULL)
        {
            list=list->next;
            if(list==NULL)
            {
                printf("No Data Found!!\n\n");
                break;
            }
        }
        if(list->a==d && list->next==NULL)
        {
            list=tail;
            temp=list;
            temp->prev->next=temp->next;
            tail=temp->prev;
            printf("Data Deleted\n\n");
            free(temp);

        }
        else if(list->a==d && list->next!=NULL)
        {
            temp=list;
            temp->prev->next=temp->next;
            temp->next->prev=temp->prev;
            temp->next=NULL;
            temp->prev=NULL;
            printf("Data Deleted\n\n");
            free(temp);
        }

    }

}
void Delete_Position()
{

    int loc;
    node *list=head,*temp;
    printf("Enter your desired Position:");
    scanf(" %d",&loc);
    if(head==NULL)
    {
        printf("Invalid Position to delete!!\n\n");
    }
    else if(loc==1)
    {
        if(list->next==NULL)
        {
            printf("Data Deleted\n\n");
            free(list);
        }
        else
        {
            head=list->next;
            head->prev=NULL;
            printf("Data Deleted\n\n");
            free(list);
        }
    }
    else
    {
        loc=loc-2;
        while(loc!=0 && list->next!=NULL)
        {
            list=list->next;
            loc--;
            if(list==NULL)
            {
                printf("No Data Found!!\n\n");
                break;
            }
        }

         if(list->next->next==NULL && loc==0)
        {
            temp=tail;
            tail=tail->prev;
            tail->next=NULL;
            printf("Data Deleted\n\n");
            free(temp);
        }
        else if(list->next->next!=NULL && loc==0)
        {
            temp=list->next;
            temp->next->prev=list;
            list->next=temp->next;
            printf("Data Deleted\n\n");
            free(temp);
        }
    }

}

void Search_Data()
{
    node *list=head;
    int s;
    printf("Enter Your number:");
    scanf("%d",&s);
    if(list->a==s)
    {
        printf(" Data Found: %d\n\n",list->a);
    }
    else
    {
        while(list->a!=s)
        {
            list=list->next;
            if(list==NULL)
            {
                printf("No Data!!\n\n");
                break;
            }
        }
        printf("%d\n\n",list->a);
    }
}


void display_first()
{
    node*list=head;
    if(head==NULL)
    {
        printf("No Data to show\n");


    }
    else
    {
        while(list!=NULL)
        {
            printf("%d\n",list->a);
            list=list->next;
        }
    }
    }