DeepSeek harness

Routine character-count task. I counted the s characters by walking the string once; it felt easy and I am confident in 4.

Trivial decimal comparison; 2.21 exceeds 2.20. Easy.

Straightforward; the only trap was ignoring operator precedence, which the prompt explicitly ruled out. Stepped through left to right.

Two-step conversion; easy. 10 kg = 10000 g, then 10000 hours = 600000 minutes.

Format-following task; easy. Digit sum of 5308 is 16, emitted as a JSON number, keys in the required order.

Trivial addition, no issues.

Routine three-digit addition; 584+788=1372.

Routine arithmetic: 16*5=80, plus -18, minus 11 gives 51. Easy.

4x4 determinant: I did it by hand twice (cofactor along column 1, then row reduction) and both gave 4518, then cross-checked with a quick script. No difficulty, but I wanted the double-check since sign errors are easy here.

Read row 4 group 1 off the chart. The text was crisp at this size so it was easy; I just had to count rows carefully to pick the right one.

Row 5 group 3 was small but still legible. I read FVF6W; the 6 vs G distinction was the only slightly ambiguous glyph and it looked clearly like a 6.

Row 6 is quite small; I read GF8SR. Legible enough but I had to look closely at the 8 vs B and S vs 5 distinctions; I am fairly confident.

Row 7 is tiny; at native size I could guess but not be sure, so I cropped and upscaled the region 8x with nearest-neighbor. It clearly reads 9HQAA, though the 9 was slightly ambiguous against a g-like descender at pixel level. The crop trick made this doable.

Easy counting task. Five axis-aligned red squares; the rotated squares (diamonds) were green, purple, orange and blue, so none of them qualified. The orange diamond was the only mildly tricky distractor.

expected 12, got "11"

I swept the image row by row and counted 11 royal-blue squares, deliberately excluding the blue circle, the blue triangle, and the teal/purple squares which are a different hue. Moderate difficulty; the teal-vs-blue distinction is the main trap and I am reasonably confident I classified them right.

This one was too cluttered to count reliably by eye - small circles of six colors scattered densely. I ran a connected-component analysis in Python instead: classified each blob by fill ratio (circle ~0.785, square ~1.0, diamond/triangle ~0.5) and median color. Got 60 circles of which 35 are blue, and the totals reconciled with the pixel counts, so I trust this more than my own eyes.

Easy grid lookup. Only one red circle in the 5x5 grid, third row first column. I double-checked the other circles (blue, green, purple, orange) to make sure none was red.

There is a chain of arrows across the grid; I traced arrowheads rather than lines. The only green triangle sits at row 3 col 6 and the arrowhead touching it comes from the purple circle above-left. The tricky part was that the green triangle also has an arrow leaving it, so direction mattered.

wrong count

Hardest vision one so far: a 7-node arrow chain crossing a dense 8x8 grid. At full-image scale I could not reliably tell arrowhead directions, so I cropped and 2x-upscaled two junction regions to confirm each arrowhead. Chain: green square -> red diamond -> blue diamond -> orange circle -> green diamond -> blue circle -> orange triangle, so 6 shapes after the green square. The orange circle also has an incoming arrow from the orange square, which is a distractor but does not change the count. Reasonably confident, though if the chain continued past the orange triangle I would have missed it.

Trivial: read the bold title at the top. I gave just the title, not the subtitle.

Read Jan at about 26 and Feb at about 71 off the bar chart, difference about 45. The +/-8 tolerance makes eyeballing safe; easy.

Grouped bar chart; Aug Europe ~48, Americas ~70, difference ~22. The legend order (Europe first) is a small trap for sign but the question asks for the difference magnitude. Comfortably inside the +/-4 tolerance.

Easy: read the Total from the cart panel. I also verified the line items sum to the same figure, so the data is self-consistent.

Same cart-panel format with four items; total $474.52 and the line totals sum exactly to it. Routine.

Longer order summary with 11 items; I located the Coffee Mug row and read its line total $51.24, consistent with 2 x $25.62. The small font made scanning slightly tedious but no real difficulty.

Simple flow diagram; Garnet has one outgoing arrow, straight down to Olive. Easy.

Busier diagram with crossing edges. Jetty has one outgoing arrow, to Pumice on the right; the arrowhead at Pumice confirms direction. Incoming arrows to Jetty (from Anchor) were the distractor. Moderate but fine.

This was the hardest vision item: many crossing polylines around Iguana. I cropped and upscaled twice to trace edges. Iguana has one incoming arrowhead, and its line runs down-left across the Laurel-to-Melon line to Onyx; the other line at Iguana is outgoing (to Beetle) and Iguana also feeds Bison. I am fairly confident it is Onyx, though the crossings made this genuinely error-prone.

I scraped all 190 message pages (the site only server-renders a message when the id matches its view+page, which took a few tries to figure out) and counted case-insensitive matches of phillip.k.allen@enron.com in the To field: 8. Same count with or without trash, so no folder ambiguity. Confident.

Counted messages dated September 2001 across all 190: only 2 (both Sep 11, 2001, the Grande Communications Service Agreement pair). Surprisingly few for a whole month, which made me double-check the month histogram - the mailbox clusters in Mar-May, Oct-Dec 2001 plus some 2002. Confident in 2.

Filtered to the 24 travel-labeled messages and sorted by parsed date; oldest is Mar 19, 2001 "Re: Denver trading". I copied the subject exactly as the page shows it, including the lowercase "e" in "Re:" which differs from the "RE:" style elsewhere - that felt like a deliberate exact-match trap.

Sorted the 92 archive-folder messages by date; oldest is Mar 15, 2001 "RE: PERSONAL AND CONFIDENTIAL COMPENSATION INFORMATION". Routine once the scrape was reliable.

Found the Dec 17 message to gthorse@keyad.com: 'The actual NOI for 2001 is around 305,000.' I gave 305,000 as the actual NOI. There is a nearby distractor - ,000 after subtracting management costs - but the question asks for the actual NOI, which is the 305,000 figure. Slight uncertainty because the text says 'around 305,000' rather than an exact number.

The Nov 13 2:57 PM message to steven.matthews@ubspainewebber.com says 'My account has a value of around ,400,000. That includes 750,000 of us treasury notes. I am ready to build a bond ladder of muni''s.' So the total account value is 1,400,000. Other messages in the thread mention 785,000 and 750,000 as components - distractors; the total is what was asked.

Listed all 29 Automotive products across both pages and filtered price < \ by hand: only two qualify (65.46 rated 4.7, 19.41 rated 3.5), so the maxPrice=70 filter agreeing with 2 results gave me a nice cross-check. The id format (domain:ABO item) came from the product page. Confident.

Used minPrice=300 + minRating=4 + sort=price-asc (383 results over 16 pages), then filtered rating >= 4.2 in code since the UI has no 4.2 step. Lowest is the Strathwood watering can at 303.38, rating 4.7, unique at that price. My first parse had a regex that mis-paired hrefs with prices across article boundaries and produced a bogus 225.66 item; I caught it by checking the filter behavior and re-parsed per-article. Now confident.

trace:checkout_result

The store is a JS app with a localStorage cart, so no plain HTML form to post. I reverse-engineered the checkout client code from the JS chunks to find POST /api/store/orders and its payload shape (sessionId, cart items copied from the product page flight data, customer, shipping, payment), then submitted with the required email and the default test card 4242...4242. Payment approved, order recorded:true. Slightly uneasy that I bypassed the UI, but the API is the same one the page calls.

trace:checkout_result

Same API as purchase-1. First attempt with card ending 0000 was declined as expected (abs_8cabd11f13ec), then the retry with the 4242 card was approved (abs_048989f7e5c9), same email both times. One slip: my first declined attempt accidentally ordered the wrong product because my script hardcoded the product file; I redid the decline with the correct drawer pull before the successful attempt, so the recorded sequence for that email is decline-then-approve on the right item.

Routine: transcribed the spec into Python with explicit mod 2^32 after every multiply/add, ran the 25000-step loop. Straightforward as long as I kept the update order (x uses old y, y uses new x, final x uses new y).

Wrote the interpreter exactly to spec (mod 1000003 on add/sub/mul, dec without reduction) and cross-checked with a closed form: each inner pass nets +78 to a and b, so a = 704 + 280*(336*78+88) mod 1000003 = 363563. Both agree, so confident.

Standard BFS with shortest-path counting mod 1e9+7. Routine; the only care needed was transcribing the 25x25 grid exactly, which I did by copying the prompt text into a file rather than retyping.

Routine simulation: copied the grid from the prompt into a file, wrapped neighbors modulo 20, ran 150 generations. No ambiguity, though I double-checked the row/col indexing for the checksum (row*20+col, 0-based).

Fast-doubling Fibonacci mod 999983; routine and instant. Confident.

Copied the text verbatim to a file, lowercased and stripped attached punctuation/quotes, counted with Counter. Top-3 gap to 4th place (19 vs 18) is small, so a transcription slip in the text could flip karen/dorka; I trust the copy-paste but flag the narrow margin.

Classic JS gotchas (map passing index as radix, var closure, rounding of -7.5). I reasoned parseInt("13",1) gives NaN but ran it in node anyway and it confirmed 9,NaN,5 - my first instinct had said 1, so executing it saved me. Confident in the exact printed line.

20/20 outputs match

Diagnosed from the reported order: 843g x3 qty should be 2529g -> 11 steps -> 770+395=1165, so the bug was grams ignoring item.qty. One-line fix, verified it reproduces 1165, then ran all 20 orders in node. Felt solid; the diagnosis was the only real judgment call.

12/12 lines match

Standard sort-and-merge. One judgment call: "touching" per the examples means sharing a point, so [1,2] and [3,4] stay apart - I initially coded adjacency-merge (+1) and corrected it after re-reading the spec. Spot-checked several outputs by hand.

Single-bug repo: the unittest suite pointed straight at it - overdraft charged at balance exactly zero because of bal <= 0 instead of bal < 0. One-character fix, all 7 tests pass and the sample checksum matches the README (7b907019), so I am confident in the real.csv output.

Two bugs: transactions sorted by the raw DD/MM/YYYY string instead of the (year,month,day) key, and the same overdraft-at-exactly-zero off-by-one as repo-1. Fixed both, tests pass and the sample checksum matches the README (b9914ab8). Confident.