Traverse in the range [ 0 , N - 1 ]
for i in range ( n ) : NEW_LINE INDENT rowSum += b [ i ] [ 0 ] NEW_LINE colSum += b [ 0 ] [ i ] NEW_LINE rowSwap += b [ i ] [ 0 ] == i % 2 NEW_LINE colSwap += b [ 0 ] [ i ] == i % 2 NEW_LINE DEDENT