Today was the day of my sudoku heat – it turned out it was the very last regional final in this year’s Independent Sudoku Grand Master Championship.

Having killed time after work in the National Library and had a dinner of traditional brain food – at Burger King – I headed off to find the hotel where the heat was being held. I walked up Leith Street and on to Leith Walk and could feel the heat and the air pollution from the major A-road making my already sore throat dry and my eyes start to react. I soldiered on but failed to find the hotel. Only once I had walked down a steep flight of steps, back up a steepish road and completely doubled back on myself did I realise I’d walked straight past it. I then proceeded to get slightly lost in the maze of corridors within the hotel. Not a good start.

Nevertheless, I got there with plenty of time to spare and registered. We had ten minutes to late so I worked on theguardian‘s quick crossword and kakuro puzzle to pass the time. A few people passed out from the previous session. Before long, we were ushered into the exam room.

The format was the same as last year, although there were fewer people in my session. It was exam conditions, 45 minutes to complete four standard 9×9 sudoku grids, the fastest 60 nationwide going through to the final in London in July.

Almost immediately I was tempted to put a number in the wrong place but stopped myself. Quickly adjusted eyes to the size of the grids (it matters) and rattled through the first two puzzles. The third was the tricksiest, although only because I wrote the wrong number in one square and, although I realised straight away, it then distracted me whenever I looked at that column. More haste, less speed – but when you’re against the clock it’s risky to go slower. The fourth puzzle pleasingly straightforward and I was done. I briefly considered checking through all the grids but decided it would take too much time: if they were right, I’d have lost valuable seconds; if wrong, they’d take so long to fix I’d probably be out of the running anyway.

I was the first to finish of the ten or so people in the room, taking somewhere between 20 and 25 minutes. Picked up my goody bag, which included a t-shirt to complement last year’s and a nice pen and pencil, and headed towards the station. I had that sudden post-match rush as I walked, realising my heart was pounding from the mental exertion, and recalled having exactly the same feeling after last time. I didn’t qualify for the final then, but I’m sure I did better this year – although that just means I’ll be more disappointed if I miss out again. The fewer entrants this year could mean fewer hardcore sudokuists – or it could mean fewer casual players.

All in all, quite an exciting day – and the week’s not over yet.