structure

#include<stdio.h>
#include<stdlib.h>
typedef struct data
{
    int a;
    data *next;
} data;
data *head;

void insert_at_end(int b)
{
    if(head==NULL)
    {
        head=(data*)malloc(sizeof(data));
        head->a=b;
        head->next=NULL;
        return;
    }
    data *temp=head;
    data *x=(data*)malloc(sizeof(data));
    x->a=b;
    x->next=NULL;
    while(temp->next!=NULL)
    {
        temp=temp->next;
    }
    temp->next=x;
}


void insert_at_begining(int c)
{
    data *x1=(data*)malloc(sizeof(data));
    x1->a=c;
    x1->next=head;
    head=x1;
}

void insert_at_n(int d,int n)
{
    data *temp=head;
    data *x2=(data*)malloc(sizeof(data));
    x2->a=d;
    if(n==1)
    {
        x2->next=head;
        head=x2;
    }
    else
    {
        n=n-2;
        while(n--);
        {
            temp=temp->next;
            if(temp->next==NULL)
            {
                temp->next=x2;
                x2->next=NULL;
                return;
            }
            x2->next=temp->next;
            temp->next=x2;
        }
    }
}

void delete_n(int m)
{
    data *temp=head;
    data *fr;
    if(m==1)
    {
        fr=temp;
        head=fr->next;
        free(fr);
    }
    else
    {
        m=m-2;
        while(m--)
        {
            temp=temp->next;
            if(temp->next==NULL)
            {
                printf("Not found\n");
                return;
            }
        }
        fr=temp->next;
        temp->next=fr->next;
        free(fr);
    }
}

void print()
{
    data *temp=head;
    while(temp!=NULL)
    {
        printf("%d ",temp->a);
        temp=temp->next;
    }
    printf("\n");
}

int lookfor(int key)
{
    data *temp=head;
    int count =0;
    while(temp->next!=NULL)
    {
        count++;
        if(temp->a==key)
            return count;
        temp=temp->next;
    }
    return -1;
}

void dltvalue(int del)
{
    data *temp=head;
    data *fr;
    int n=lookfor(del);
    if(n==1)
    {
        fr=temp;
        head=fr->next;
        free(fr);
    }
    else
    {
        n=n-2;
        while(n--)
        {
            temp=temp->next;
            if(temp->next==NULL)
            {
                printf("Not found\n");
                return;
            }
        }
        fr=temp->next;
        temp->next=fr->next;
        free(fr);
    }

}
int main()
{
    int del,b,c,d,n,t,key;
    head=NULL;
    printf("1. insert\n");
    printf("2. begening\n");
    printf("3. insert_n\n");
    printf("4. delete_n\n");
    printf("5. print\n");
    printf("6. find\n");
    printf("7. delete\n");
    while(1)
    {
        scanf("%d",&t);
        switch(t)
        {
        case 1:
            scanf("%d",&b);
            insert_at_end(b);
            break;
        case 2:
            scanf("%d",&c);
            insert_at_begining(c);
            break;
        case 3:
            scanf("%d%d",&d,&n);
            insert_at_n(d,n);
            break;
        case 4:
            int m;
            scanf("%d",&m);
            delete_n(m);
            break;
        case 5:
            print();
            break;
        case 6:
            {
                scanf("%d",&key);
                int z=lookfor(key);
                if(z!=-1) printf("Element Found\n");
                else printf("Element Not Found\n");
                break;
            }
        case 7:
            scanf("%d",&del);
            dltvalue(del);
            break;
        }
    }
    return 0;
}