Skyscrapers puzzle solver
Type the clues from any skyscrapers (towers, skyline) puzzle and get the answer, a count of how many answers exist, and a step-by-step explanation of the logic. It runs in your browser: nothing you type is sent anywhere.
How the solver works
The solver looks at one row or column at a time. For a line with its two clues and the heights that are still possible in each cell, it lists every order of 1 to N that would satisfy both clues, and keeps only what all those orders agree on. It repeats this on every row and column until nothing more changes. This is the same reasoning a person uses, done exhaustively. If the board is not finished by then, it tries each possibility for one cell and counts the complete answers it finds, up to two, so you learn whether the puzzle has exactly one answer, several, or none.
The result says "exactly one answer" only when its search found one and ruled out every other. Clues you mistype can make a puzzle unsolvable, and the solver then reports "no answer", which is a good prompt to re-check the numbers against your puzzle. For help doing it by hand, read the guide to solving skyscrapers puzzles, or play today's board on the Vantage daily puzzle. The source is available as a small open-source command-line tool too.