advantages of link-based sequences link-based structures provide worst-case time bounds for their operations this is in contrast to the amortized bounds associated with the expansion or contraction of dynamic array (see section when many individual operations are part of larger computationand we only care about the total time of that computationan amortized bound is as good as worst-case bound precisely because it gives guarantee on the sum of the time spent on the individual operations howeverif data structure operations are used in real-time system that is designed to provide more immediate responses ( an operating systemweb serverair traffic control system) long delay caused by single (amortizedoperation may have an adverse effect link-based structures support ( )-time insertions and deletions at arbitrary positions the ability to perform constant-time insertion or deletion with the positionallist classby using position to efficiently describe the location of the operationis perhaps the most significant advantage of the linked list this is in stark contrast to an array-based sequence ignoring the issue of resizing an arrayinserting or deleting an element from the end of an arraybased list can be done in constant time howevermore general insertions and deletions are expensive for examplewith python' array-based list classa call to insert or pop with index uses ( time because of the loop to shift all subsequent elements (see section as an example applicationconsider text editor that maintains document as sequence of characters although users often add characters to the end of the documentit is also possible to use the cursor to insert or delete one or more characters at an arbitrary position within the document if the character sequence were stored in an array-based sequence (such as python list)each such edit operation may require linearly many characters to be shiftedleading to (nperformance for each edit operation with linked-list representationan arbitrary edit operation (insertion or deletion of character at the cursorcan be performed in ( worst-case timeassuming we are given position that represents the location of the cursor