SAT (short for "satisfiability") is a logic problem that given a boolean formula, it asks whether the boolean formula has an assignment that makes the problem true. An example boolean formula is:
Made with wood, springs and rubber bands, Rich Walker remembers fondly the first robotic hand built by Shadow Robot in the late 1990s.
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Москвичей предупредили о резком похолодании09:45
Strands, the New York Times' elevated word-search game, requires the player to perform a twist on the classic word search. Words can be made from linked letters — up, down, left, right, or diagonal, but words can also change direction, resulting in quirky shapes and patterns. Every single letter in the grid will be part of an answer. There's always a theme linking every solution, along with the "spangram," a special, word or phrase that sums up that day's theme, and spans the entire grid horizontally or vertically.