I have made a circular queue where data can be pushed or popped on either end of a vector of structs. Adding an entry can be done on the end or the head withou

I have made a circular queue where data can be pushed or popped on either end of a vector of structs. Adding an entry can be done on the end or the head without moving any other nodes. All that is required is to have an index for the head and one for the tail. Used as a queue, you would push nodes on the tail and pop nodes off the head. You could just as easily add nodes to the head and pop them off the tail or any combination that you like. You could iterate over the list by starting at the tail and moving backward toward the head. You could also start at the head and move forward toward the tail. If you try to move below the first element then set the index to the last entry. If you try to move above the last entry then continue on the front of the vector. If the head and tail have the same number then no entries are in the vector. If the buffer size (which determines how many entries you can have) is about to be exceeded then create a bigger buffer and copy the old entries to the new buffer. Instead of creating a bigger buffer and copying all the entries, you could make a new "cluster" of the same size as the current buffer and then you could use an integer division and modulo to determine in which cluster and what offset any node might be at. Using the cluster method, the whole struct could grow as needed, and never move any existing data entries while pushing/popping data at either the head or tail of the list of array nodes. The struct could be just a single number or any other sized structure. Memory allocations would be minimized by allocing a buffer of "n" times the size of each node.