Claude Opus 5.5 (effort default (no --effort flag) · thinking on) on Boat fuel range with a reserve over a planned trip

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  "result": "I wrote `solve.py` and ran it on `input.json`, which produced `answer.json`. I checked a few values by hand and tried one made-up input where a leg can't be run. I don't have the hidden checks, so this hasn't been scored.\n\n**Results for the given input:**\n- **Reserve:** 60 L (20% of the 300 L tank).\n- **Reserve breach:** after leg 4, when 27.96 L is left.\n- **Runs dry:** during leg 5, 9.31 nm in. It starts that leg with 27.96 L, needs 42.32 L, burns 19.66 L/h and makes 6.55 kn over the ground.\n- **Leg 6:** still processed as the rules say; the trip ends at \u221254.32 L.\n- **Economy:** 1400 rpm gives the best mileage, 0.6429 nm per litre. That's a range of 124.71 nm on the 194 L above the reserve.\n\n**Edge-case test:** I edited the input so leg 1 runs against a 20 kn current (a negative speed over the ground). The script stopped at that leg, wrote empty hours and fuel for it, and marked it as the dry leg at 0 nm.\n\n**Choices the rules didn't settle (any could differ from the hidden checks):**\n- **Reserve check on a stopped leg:** the leg that can't be run still counts. If fuel left on it is below the reserve and no breach has been recorded yet, it becomes the breach leg. This only matters if you start with less than the reserve.\n- **Distance before running dry:** never reported as negative. If the fuel left at the start of the leg is already zero or below, it shows 0.\n- **Economy table:** rows that burn zero litres per hour are skipped. The range uses the unrounded nm-per-litre figure.\n- **Duplicate rpm rows:** if the table lists the same rpm twice, the script uses the first of those rows rather than averaging.",
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