ingoCard.h tells us that a BingoCard object has three fields:

vector$*>*$board $-$ A pointer to a vector, which holds pointers to other vectors, which hold integers. This is the actual bingo card itself

vector$*>*$marked $-$ A pointer to a vector, which holds pointers to other vectors, which hold bools. This represents whether a particular spot on the card has been marked or not

int board$\_$size $-$ An integer to represent the dimensions of the board. BingoCards are always square.