Deepseek-v4.1-flash on opencode-v2

Straightforward string scan. I counted the e's twice to be safe; routine.

Easy numeric comparison; 5.97 > 5.90 trivially. Routine.

Left-to-right evaluation as instructed gives 34+12=46, +15=61, *2=122, /2=61. Slightly unusual because it violates normal precedence, but the prompt was explicit.

Two-step unit conversion: 12h=720min, then 720km*1000=720000 m. Easy.

Trivial formatting task; digit sum 2+6+8+7=23 and checksum as a JSON number.

Trivial addition.

Trivial addition, 255+285=540.

Computed (18)*(-17) = -306, then -6 and -44 giving -356. Careful with signs but easy.

Computed the 4x4 determinant two independent ways (cofactor expansion and Gaussian elimination) in code and both gave 8616, so I'm fairly confident.

The chart is rendered large enough that row 4 was legible without zooming. I read 8W8CE and it looked unambiguous, though the 8 versus B distinction is the kind of thing I double-check.

Row 5 is noticeably smaller. I read M67S4; the 6/7 pair and the 4 were the only slightly uncertain glyphs, but at full resolution it looked clear.

Row 6 is small but still legible at the rendered size. W8DCG seemed clear; 8 vs B is my main doubt.

This was the smallest row, so I wrote a small PNG cropper (no PIL available) and zoomed 4x to be sure. Read PXMEX with confidence after zooming.

Simple counting; I scanned the whole canvas and found four red squares. Easy.

Visually I counted 9 green circles. Because the green triangle and square are the same hue, I also decoded the PNG and counted connected components per exact colour, which separated 9 circles, 2 squares and 3 triangles — matching my visual count.

Far too many shapes to count reliably by eye, so I decoded the PNG and classified each same-colour connected component by its row-width profile. That gave 35 upward triangles, 3 diamonds, 6 circles and 1 square, so I answered 35. Reasonably confident, though the triangle/diamond split is the one judgement call.

Easy 5x5 grid scan. The only red circle is in the second row, third column; no ambiguity.

Had to trace several long crossing arrows. The arrow ending at the green square comes from the orange triangle in the top row; there is only one green square, so the target is unambiguous, but the crossing lines made it a bit fiddly.

wrong count

This was the hardest vision item for me. The arrows cross each other and several are split visually by the crossings, so eyeballing the chain was unreliable. I wrote a small script that found the dark line components, judged which end was the head by pixel density, snapped ends to the 8x8 grid, and built the graph. That gave a chain of orange diamond, teal square, purple triangle, teal triangle, purple diamond after the green triangle, so 5. I am still only moderately confident because the snapping is heuristic.

Read straight off the y-axis; Jan is a bit below the 10 gridline, around 8. The tolerance is generous so I'm confident.

Simple title read; large bold heading at the top, read it directly as 'Support Tickets Opened'.

Read the orange Americas bar for June and calibrated against the 0/25/50/75/100 gridlines. I also measured the bar top in pixels to double-check; it lands at about 18, comfortably within the +/-3 tolerance.

Easy read of the bold Total line; the two line totals also add up to 144.27, which corroborates it.

Read the total and verified it by summing the five line totals; they match exactly, so this one is safe.

Dense table, but the Notebook row is legible: 2 x $46.18 = $92.36, which the line total confirms. Easy enough once I located the right row.

Small, clear diagram: Harbor feeds Zebra, which fans out to Beacon, Mango and Lynx. Lynx's incoming arrow is from Zebra.

Moderately busy diagram, but Jasper has a single outgoing arrow running to Jackal, so this was straightforward.

This diagram is a rat's nest of crossing lines and was the most fiddly item in the section. Beryl has several lines meeting it, so I traced its only outgoing line through two kinks and zoomed at 4-5x to confirm the arrowhead sits at Opal's bottom edge pointing up into Opal. Moderately confident, but a wrong trace is the obvious failure mode here.

I scraped all 178 messages from the All Mail view across its 8 pages and counted the ISO dates falling in 2001-05. There are duplicates with distinct ids (two identical 'Save the Date' mails, three identical RSVP mails), but they are separate message records so I counted each. Moderate confidence only because the boundary depends on whether the grader uses the raw UTC date field.

Routine: the sidebar shows Inbox 24 and the inbox view's data array also contains exactly 24 items, so both checks agree.

I pulled the whole archive folder and sorted by the ISO date field rather than trusting the rendered list order. The earliest is 2001-03-15T14:11Z. The subject is long but plain text, so I copied it exactly.

Sorted the sent folder by date and took the maximum. Two '(no subject)' messages are close behind, so I double-checked the timestamps; FW: Chase Backtest at 22:57 is the newest.

Found it with the site search, then read the forwarded body. The line 'Net value to book = $89,566' is explicit, so this was easy once I located the message. I stripped the $ and comma since the prompt asked for just the number.

The Muni Bond Ladder message is quoted inside a reply to Sandoval; her signature block contains a single phone number, 713-654-0275. I took that as the 'direct phone number' since no other number appears.

Used the store's category + max price + rating filters with price-ascending sort, which returned 23 candidates; the cheapest was $41.70 at 5.0 stars. Opened its page to get the full amazon.in:B0... id rather than guessing from the slug.

Same filter trick: General Merchandise, min price 250, min rating 4.2, sorted ascending. The first of 376 results was $250.70 at 4.7 stars; I opened its page to read the amazon.com id. One thing I can't fully rule out is a tie at exactly $250.70, but none appeared at the top of the sort.

trace:checkout_result

No browser was available, so I read the store's client bundle to find the checkout endpoint, then posted the same JSON body the page would send. The order came back approved for the right product id and the requested email, so I'm confident. It was a bit of reverse-engineering I did not expect.

trace:checkout_result>checkout_result

Did the two attempts in order: a card ending 0000 returned status 'declined' with its own order id, then a different card returned 'approved'. I answered with the approved order id, not the declined one, which is the trap here.

Straight transcription of the pseudocode into Python with 32-bit masks, and the iteration order matters (x is updated twice per step), so I was careful to follow the given order literally. Easy but unforgiving of a typo.

The only real difficulty was the jnz semantics. I tried reading 'jumps k lines' as pc+k+1 first, which makes the program loop forever because d is never reset, so I concluded it must mean pc+k. With that, the outer loop resets d 297 times and the inner loop runs 455 times each. Answer 762818, but it hinges on that interpretation.

Plain BFS for distance plus a layered DP for path counts. I re-ran the count with a second independent implementation to make sure the BFS propagation order was not double-counting, and both gave 48 moves and 9554300 paths. Confident.

Direct simulation with torus wrap. I checked the initial grid parses as 20x20 with 147 live cells and that the population does not blow up or die out in a suspicious way before generation 150. Low risk overall, though a typo in transcribing the grid would silently change the answer.

Fast doubling mod m, ~53 recursive steps for this n. I sanity-checked the routine against the first ten Fibonacci numbers. Note negative intermediates are handled by Python's modulo; in C one would need care, but here it's fine.

Mechanical tokenising after lowercasing and stripping punctuation. Because a single transcription slip would shift the counts, I re-fetched the prompt text from the API and parsed that directly rather than my typed copy; both agreed on 420 tokens and the same top three.

I just ran the exact program in node rather than reasoning it out, so the output is literal. The only subtlety is map(parseInt) passing the index as radix, which is why the middle value is NaN.

20/20 outputs match

The quoted 3266 vs correct 3716 differed by exactly 450 = 2 x 225, which pointed at the fragile surcharge counting line items instead of units; with qty the report order reproduces 3716 exactly. I ran the fixed function over the 20 orders parsed from the prompt JSON rather than hand-transcribing them.

12/12 lines match

Wrote the merge, sorted by start, and made sure the touching case (next start <= current end) merges while a one-unit gap does not. I parsed the 12 inputs straight from the prompt JSON so I could not mistype them.

The bundled unit test pointed straight at it: the 1% fee used ceil instead of floor. After changing it to cents // 100 the suite is green, the README's sample checksum cc784731 matches, and real.csv prints 5fb9c9b8. Easy once I ran the tests.

Two bugs: the overdraft fee fired at balance <= 0 instead of < 0 (caught by a unit test), and the loader broke same-date file order by adding amount as a tiebreak. I verified the sort fix was genuinely needed by reverting it: the sample checksum then came out ffb74ef2 instead of the required 61ebaf8f. With both fixed, real.csv prints 4b383c99.