The implementation of the sequential search depends on the underlying storage structure. It is possible to implement the algorithm using any type of structure, as long as the search process visit each record sequentially. But, we only present the implementation using linked list and array. Other structures are associated with their own searching strategy, which may not be sequential as well. The implementation using linked list uses the following mechanisms.
Indices are pointers.
The next function can be implemented by updating the return value to point to the next record. However, the next function should be able to access the last value in order to check with the storage boundary. Usually, it will use the membership function of the abstract data type associated with the record. But, the function returns a compound value of the entire record. The Print function, as a method of the abstract type, should be able to output the compound value.