atoi

struct node * insert2(struct node *root, char x[],char id[])
{


    if(!root)
    {
        root=(struct node*)malloc(sizeof(struct node));
        free( root->data );                // free previously allocated memory, if any
        root->data = strdup( x ); // malloc and copy
        root->id=id;
        root->left = NULL;
        root->right = NULL;
        //   printf("1\n");
        return(root);
    }

    if(atoi(root->id) > atoi(id)){
        root->left = insert(root->left,x,id);
    }
    else
    {
        if(atoi(root->id) < atoi(id))
            root->right = insert(root->right,x,id);
    }
    return(root);
}