sequential search(Search and Insertion)

[mehak]

sequential search(search and insertion)

#include <iostream>
using namespace std;
struct node
{
    int key;
    int record;
    node *link;
};
typedef struct node* list;
void print(list head)
{
    int i=1;
    list temp=head;
    cout<<"\nThe records and their associated keys are\n";
    cout<<"i"<<"\t"<<"key"<<"\t"<<"record"<<endl;
    while(temp!=NULL)
    {
        cout<<i<<"\t"<<temp->key<<"\t"<<temp->record<<"\n";
        i++;
        temp=temp->link;
    }

}
void searchAndInsert(list *head,int key_value)
{

    int rec_value;
    list temp,s;
    if(*head==NULL)
    {
        temp=new node;
        cout<<"\nEnter record : ";
        cin>>rec_value;
        temp->record=rec_value;
        temp->key=key_value;
        temp->link=NULL;
        *head=temp;
        return;
    }
    temp=(*head);
    while(temp!=NULL && (temp->key)!=key_value)
    {
        s=temp;
        temp=temp->link;
        //cout<<"ji";
    }
    if(temp!=NULL)
    {
        cout<<"\nrecord found";
    }
    else
    {
        temp=new node;
        cout<<"\nEnter record : ";
        cin>>rec_value;
        temp->record=rec_value;
        temp->key=key_value;
        s->link=temp;
        temp->link=NULL;
    }
}
int main()
{
    int key_value,n;
    list head=NULL;
    while(1)
    {
        cout<<"Enter the key you want to search :";
        cin>>key_value;
        searchAndInsert(&head,key_value);
        print(head);
        cout<<"\n\nanother search?(1/0) : ";
        cin>>n;
    }

}

[MiiNiPaa]

Switch && operands. Checking for null pointer should be done first.

[mehak]

thnx alot :)

[Chervil]

If the pointer is NULL it isn't even possible to evaluate the other operand. That's why it must be done first.

[MiiNiPaa]

temp->key can crash if you will try to apply it to the null pointer.
If you make temp != NULL it wil stop if it will evaluate to false (if temp is a null pointer) and will not execute second part, saving you from undefined behavior.

[mehak]

plzz hav a look..the first while loop is not working

[Chervil]

Could you please explain what is meant by "not working".

[mehak]

thnx for the help...cud u plz help me with my first while loop also

[mehak]

run time error

[Chervil]

Run time error caused by trying to de-reference a NULL pointer?

[mehak]

em sorry but i din get u

[MiiNiPaa]

compare lines 31-37 and 53-58. You forgot to set one field.

[mehak]

thnx alot :)