Mark Sweep's puzzles

If you're here just for the practice puzzles, scroll all the way down to the bottom of this post. This post is also quite late after the WSPC, but I just did not have the time and motivation to finish up this post earlier. This was my third time participating at the world championships, being part of the Dutch B-team for Sudoku and the Dutch A-team for Puzzles. In general, I immensely enjoyed this event. It was very well organized, went smoothly, and most puzzles were of very high quality! So huge credits to the organization and author teams for making this happen.  WSC 2025 Individual ranking: 82nd/252 Team ranking: 17th/63  It was a nice surprise to me that I placed top 100 in Sudoku, considering I had not solved many prior to this championship (as all my practice goes into WPC). I did love the variation between rounds, with several rounds feeling quite different from regular Sudoku. For me that's perfect, as the weirder or more puzzle-like it gets, the better I tend to be a...

Currently catching up with posting some puzzles on this blog. Like in 2023, in 2024 I helped to create puzzles for the UK puzzle championship (UKPC). The championship was divided into two rounds of 90 minutes each, with 540 points up for grabs in each round (so 6 points per minute). Round 1 can be found  here  and round 2 can be found  here .  Below you can find the puzzles I created. 1.2 Suguru (15 points) Rules Place a number into each cell so that each region contains the numbers from 1 to N with no repeats, where N is the number of cells in the region. Numbers of the same value may not touch one another, not even diagonally. Solve on Penpa 1.5 Country Road (18 points) Rules Draw a non-intersecting loop through the centers of some cells which passes through each region exactly once. A number in a region represents how many cells in the region are visited by the loop. Orthogonally adjacent cells across a region border may not both be unused. Solve on Penpa 1.11 Co...