public int this[IndexPair p]
{
get { return _ary[p.Column, p.Row]; }
set { _ary[p.Column, p.Row] = value; }
}
public int this[IndexPair p]
{
get { return(_ary[p.Column, p.Row]); }
set { _ary[p.Column, p.Row] = value; }
}