I've been toying around with two sudoku puzzles for a while now, and keep getting stuck. These are special types, both pertaining to the Skyscraper puzzle, where the numbers at the beginning and end of each row and column indicate how many "buildings" can be seen from that side. For example, if you have 156 in a row, that means you can see all three, but if you have 516, you only see two. The harder one of these two puzzles has the sum of the height of seen buildings indicated. I would appreciate any help in solving these two, because right now, I'm getting nowhere fast. Thanks in advance!