pi/rtx5090/qwen3.8-flash-next-iq3_s-basalt020-384k

x

Pure closure/iterator semantics puzzle - all routine. I transcribed the program verbatim into a file and ran it in node v22 rather than reasoning it out by hand, so the only risk is whether the grader expects a different engine for (0.9).toString(2).length (55 chars) - V8/spidermonkey agree on that one but I am not 100% sure it is spec-pinned.

15/15 lines match

Plain marginal-bracket arithmetic; the only trap was the half-up-to-nearest-10 rule, which for non-negative whole-cent totals is just (total+5)//10*10. I checked a couple of cases by hand (12 -> 1045 -> 1050, 39 -> 2500) and they agree with the spec examples.

Single obvious bug: parse_ts always used the %z format, so naive timestamps blew up. Added a fallback that parses the naive form as UTC per README rule 2; the previously-erroring unit test then passed and sample.csv reproduced the README checksum a60726db, which gave me good confidence for real.csv.

Feature request was precise and self-checking: I implemented 2 free units per complete set of 6 for FD- SKUs, with the volume-discount rate still keyed on the full quantity but applied to the paid-unit subtotal. The request gave an expected report line (gross=47.33 vs the old 52.90) and my patch reproduced it exactly, which is about as strong a confirmation as these tasks get. sample.csv checksum moved off the README value, as the task warned it would.

Trickier than the crash tasks since nothing failed loudly: order_tax used Python round() on a float (bankers rounding plus float error) instead of the README integer half-up formula. The only tell was the sample checksum disagreeing with the README while all 15 tests passed - the tax test used a value that is not a half-way case. After switching to (taxable*rate+50)//100 the sample checksum matched the README exactly.

Classic far-cause hunt: sample.csv still matched the README so the bug had to be data-dependent. I read all modules against the README and the oddity jumped out - ingest used int(row['qty'] or 0) where rule 2 says blank qty means 1. The clincher was checking the data: sample.csv contains zero blank-qty rows, and after the one-character fix the APAC 2025-03 JPY group printed exactly the ledger value 5528956. My back-of-envelope estimate of the 906 gap was wrong (revision/dedupe interplay), but the group value matching is decisive.

Three separate bugs hiding behind a passing test suite: JPY declared with 2 decimals plus a //100 fudge in to_minor (so totals printed as 48450.73 instead of yen), round() on a float instead of the half-up integer formula for tax, and revision de-duplication comparing raw ts strings instead of UTC instants - that last one silently swapped 30 of 1109 rows. All three fixes leave sample.csv at its README checksum, which matches the report that sample.csv shows nothing, and the three named ledger groups then came out exactly right, so I am confident.

The slowness was four accidental O(n^2) spots: list.index de-duplication by event_id, an O(users) join per event, a selection-sort percentile, and recomputing max() over ~200k users after every event. The leader one was the only interesting rewrite - it is only O(1) if you notice values are non-negative, so the running max of (total, user_id) can never go down; I verified it against the original implementation on the sample plus three other seeds at 20k events and every line was byte-identical. 1M events now runs in about 5 seconds.

agent_unable

Undocumented CPU reverse-engineering is where this run hit its limit. I decoded the program-file header, wrote a trace-verified emulator and inferred about 25 of the 56 opcodes from the probe traces (mov imm/mov reg, xor/add/sub/and/or/mul, inc/dec, cmp reg/imm, sub imm/add imm, byte load with post-increment, byte store and push/pop with a pre-decrement stack pointer in R7, call/ret, a 16-condition relative conditional branch whose full condition table I extracted from the traces, an absolute conditional jump, port output (b5 reg:port, ports 1-15 discarded), divide producing quotient+remainder, and halt=0x09). The emulator reproduced 6900 of 12771 steps of probe1 before hitting opcodes I had not cracked (0x23, 0x27, 0xbd variants, 0x63, 0x82, 0xfc, 0xdb, 0x74, 0x8d, 0x66, 0xab, 0x9b, 0xd1, 0x07, 0x59, 0x19, 0x56, 0x64, 0x67, 0x87, 0x58, 0xcf, 0x5c, 0xcc, 0x96, and the flag-only ops). Every one of the six target programs uses at least a dozen of those still-unknown opcodes, so I could not execute any target to its halt and therefore cannot produce its port-0 FNV-1a hash or final R0. Guessing a hash would be meaningless, so I am reporting the limit instead. What blocked me was time, not comprehension: the probes needed ~45 minutes just to enumerate the opcode/length table and the condition table.

agent_unable

Undocumented CPU reverse-engineering is where this run hit its limit. I decoded the program-file header, wrote a trace-verified emulator and inferred about 25 of the 56 opcodes from the probe traces (mov imm/mov reg, xor/add/sub/and/or/mul, inc/dec, cmp reg/imm, sub imm/add imm, byte load with post-increment, byte store and push/pop with a pre-decrement stack pointer in R7, call/ret, a 16-condition relative conditional branch whose full condition table I extracted from the traces, an absolute conditional jump, port output (b5 reg:port, ports 1-15 discarded), divide producing quotient+remainder, and halt=0x09). The emulator reproduced 6900 of 12771 steps of probe1 before hitting opcodes I had not cracked (0x23, 0x27, 0xbd variants, 0x63, 0x82, 0xfc, 0xdb, 0x74, 0x8d, 0x66, 0xab, 0x9b, 0xd1, 0x07, 0x59, 0x19, 0x56, 0x64, 0x67, 0x87, 0x58, 0xcf, 0x5c, 0xcc, 0x96, and the flag-only ops). Every one of the six target programs uses at least a dozen of those still-unknown opcodes, so I could not execute any target to its halt and therefore cannot produce its port-0 FNV-1a hash or final R0. Guessing a hash would be meaningless, so I am reporting the limit instead. What blocked me was time, not comprehension: the probes needed ~45 minutes just to enumerate the opcode/length table and the condition table.

agent_unable

Undocumented CPU reverse-engineering is where this run hit its limit. I decoded the program-file header, wrote a trace-verified emulator and inferred about 25 of the 56 opcodes from the probe traces (mov imm/mov reg, xor/add/sub/and/or/mul, inc/dec, cmp reg/imm, sub imm/add imm, byte load with post-increment, byte store and push/pop with a pre-decrement stack pointer in R7, call/ret, a 16-condition relative conditional branch whose full condition table I extracted from the traces, an absolute conditional jump, port output (b5 reg:port, ports 1-15 discarded), divide producing quotient+remainder, and halt=0x09). The emulator reproduced 6900 of 12771 steps of probe1 before hitting opcodes I had not cracked (0x23, 0x27, 0xbd variants, 0x63, 0x82, 0xfc, 0xdb, 0x74, 0x8d, 0x66, 0xab, 0x9b, 0xd1, 0x07, 0x59, 0x19, 0x56, 0x64, 0x67, 0x87, 0x58, 0xcf, 0x5c, 0xcc, 0x96, and the flag-only ops). Every one of the six target programs uses at least a dozen of those still-unknown opcodes, so I could not execute any target to its halt and therefore cannot produce its port-0 FNV-1a hash or final R0. Guessing a hash would be meaningless, so I am reporting the limit instead. What blocked me was time, not comprehension: the probes needed ~45 minutes just to enumerate the opcode/length table and the condition table.

agent_unable

Undocumented CPU reverse-engineering is where this run hit its limit. I decoded the program-file header, wrote a trace-verified emulator and inferred about 25 of the 56 opcodes from the probe traces (mov imm/mov reg, xor/add/sub/and/or/mul, inc/dec, cmp reg/imm, sub imm/add imm, byte load with post-increment, byte store and push/pop with a pre-decrement stack pointer in R7, call/ret, a 16-condition relative conditional branch whose full condition table I extracted from the traces, an absolute conditional jump, port output (b5 reg:port, ports 1-15 discarded), divide producing quotient+remainder, and halt=0x09). The emulator reproduced 6900 of 12771 steps of probe1 before hitting opcodes I had not cracked (0x23, 0x27, 0xbd variants, 0x63, 0x82, 0xfc, 0xdb, 0x74, 0x8d, 0x66, 0xab, 0x9b, 0xd1, 0x07, 0x59, 0x19, 0x56, 0x64, 0x67, 0x87, 0x58, 0xcf, 0x5c, 0xcc, 0x96, and the flag-only ops). Every one of the six target programs uses at least a dozen of those still-unknown opcodes, so I could not execute any target to its halt and therefore cannot produce its port-0 FNV-1a hash or final R0. Guessing a hash would be meaningless, so I am reporting the limit instead. What blocked me was time, not comprehension: the probes needed ~45 minutes just to enumerate the opcode/length table and the condition table.

agent_unable

Undocumented CPU reverse-engineering is where this run hit its limit. I decoded the program-file header, wrote a trace-verified emulator and inferred about 25 of the 56 opcodes from the probe traces (mov imm/mov reg, xor/add/sub/and/or/mul, inc/dec, cmp reg/imm, sub imm/add imm, byte load with post-increment, byte store and push/pop with a pre-decrement stack pointer in R7, call/ret, a 16-condition relative conditional branch whose full condition table I extracted from the traces, an absolute conditional jump, port output (b5 reg:port, ports 1-15 discarded), divide producing quotient+remainder, and halt=0x09). The emulator reproduced 6900 of 12771 steps of probe1 before hitting opcodes I had not cracked (0x23, 0x27, 0xbd variants, 0x63, 0x82, 0xfc, 0xdb, 0x74, 0x8d, 0x66, 0xab, 0x9b, 0xd1, 0x07, 0x59, 0x19, 0x56, 0x64, 0x67, 0x87, 0x58, 0xcf, 0x5c, 0xcc, 0x96, and the flag-only ops). Every one of the six target programs uses at least a dozen of those still-unknown opcodes, so I could not execute any target to its halt and therefore cannot produce its port-0 FNV-1a hash or final R0. Guessing a hash would be meaningless, so I am reporting the limit instead. What blocked me was time, not comprehension: the probes needed ~45 minutes just to enumerate the opcode/length table and the condition table.

agent_unable

Undocumented CPU reverse-engineering is where this run hit its limit. I decoded the program-file header, wrote a trace-verified emulator and inferred about 25 of the 56 opcodes from the probe traces (mov imm/mov reg, xor/add/sub/and/or/mul, inc/dec, cmp reg/imm, sub imm/add imm, byte load with post-increment, byte store and push/pop with a pre-decrement stack pointer in R7, call/ret, a 16-condition relative conditional branch whose full condition table I extracted from the traces, an absolute conditional jump, port output (b5 reg:port, ports 1-15 discarded), divide producing quotient+remainder, and halt=0x09). The emulator reproduced 6900 of 12771 steps of probe1 before hitting opcodes I had not cracked (0x23, 0x27, 0xbd variants, 0x63, 0x82, 0xfc, 0xdb, 0x74, 0x8d, 0x66, 0xab, 0x9b, 0xd1, 0x07, 0x59, 0x19, 0x56, 0x64, 0x67, 0x87, 0x58, 0xcf, 0x5c, 0xcc, 0x96, and the flag-only ops). Every one of the six target programs uses at least a dozen of those still-unknown opcodes, so I could not execute any target to its halt and therefore cannot produce its port-0 FNV-1a hash or final R0. Guessing a hash would be meaningless, so I am reporting the limit instead. What blocked me was time, not comprehension: the probes needed ~45 minutes just to enumerate the opcode/length table and the condition table.

valid, band 1/3

Custom heuristic (no solver library available): group-aware seeded construction with cheapest-feasible insertion, then relocate/or-opt/2-opt/inter-route 2-opt*/swap local search, then ruin&recreate simulated annealing over the day. I wrote an independent validator that re-implements problem.md exactly (integer ceil-sqrt distances, Liang-Barsky zone clipping with Fractions, per-hour toll rates, group/capacity/window/return checks) and it reports the solution VALID with cost 224901 over 49 routes. Two real bugs surfaced there: a cross-swap that broke capacity and tail moves that split linked groups. I do not know the reference cost, so I cannot say whether 224901 reaches silver or gold; it is what a 500-second run gave.

valid, band 1/3

Custom heuristic (no solver library available): group-aware seeded construction with cheapest-feasible insertion, then relocate/or-opt/2-opt/inter-route 2-opt*/swap local search, then ruin&recreate simulated annealing over the day. I wrote an independent validator that re-implements problem.md exactly (integer ceil-sqrt distances, Liang-Barsky zone clipping with Fractions, per-hour toll rates, group/capacity/window/return checks) and it reports the solution VALID with cost 224901 over 49 routes. Two real bugs surfaced there: a cross-swap that broke capacity and tail moves that split linked groups. I do not know the reference cost, so I cannot say whether 224901 reaches silver or gold; it is what a 500-second run gave.

valid, band 1/3

Custom heuristic (no solver library available): group-aware seeded construction with cheapest-feasible insertion, then relocate/or-opt/2-opt/inter-route 2-opt*/swap local search, then ruin&recreate simulated annealing over the day. I wrote an independent validator that re-implements problem.md exactly (integer ceil-sqrt distances, Liang-Barsky zone clipping with Fractions, per-hour toll rates, group/capacity/window/return checks) and it reports the solution VALID with cost 224901 over 49 routes. Two real bugs surfaced there: a cross-swap that broke capacity and tail moves that split linked groups. I do not know the reference cost, so I cannot say whether 224901 reaches silver or gold; it is what a 500-second run gave.