A nondefault constructor Board$($int$**$ arr, int m$,$ int n$)1.$ If both given parameters m and n are larger than or equal to $2,$ use m and n to set data members numRows and numCols, respectively, otherwise, set data members numRows and numCols to be $3.$ Set the elements of panel to be $1,2,,$ numRows $*$ numCols$-1.$ The numbers are placed from the top row to the bottom row, and in each row, from left to right. No randomize is needed at this step. $2.$ Otherwise, dynamically apply for space to hold a numRows $*$ numCols integer array. Put the initial address in data member panel. $3.$ Set the elements of panel to be the same arrangement as that of given parameter arr. You may notice that there are a lot of common codes among those constructors. A better way is to define Board$($int m$,$ int n$).$ Then use constructor delegate to define Board$()$ and Board$($int$**$ arr, int m$,$ intors in Board.cpp The purpose of constructor is to initialize data members. A class may have multiple constructors. Different constructors have different parameter lists. Each constructor has exactly the same name as class, no return type, not even void. $2\mathrm{.}1$ The default constructor Board$()$ The default constructor does not take any parameter. It does the following: