A Utility that padds zeros in front of the Node , with the given diff
def paddZeros ( sNode , diff ) : NEW_LINE INDENT if ( sNode == None ) : NEW_LINE INDENT return None NEW_LINE DEDENT zHead = newNode ( 0 ) NEW_LINE diff = diff - 1 NEW_LINE temp = zHead NEW_LINE while ( diff > 0 ) : NEW_LINE INDENT diff = diff - 1 NEW_LINE temp . next = newNode ( 0 ) NEW_LINE temp = temp . next NEW_LINE DEDENT temp . next = sNode NEW_LINE return zHead NEW_LINE DEDENT borrow = True NEW_LINE