The Bakery Oven Timer
The OVEN turns on only if the TIMER is active and the HEAT switch is off. If the TIMER is off, the OVEN stays off regardless of the HEAT.
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The truth table
Inputs on the left, the output on the right. A circuit solves the puzzle when it reproduces every row.
| TIMER | HEAT | OVEN |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
What the table tells you
- OVEN is 1 in 1 of the 4 rows, so it is a single AND-shaped condition: one exact combination of the inputs. Every input matters: for each one there is a row where flipping it changes OVEN.
The smallest known circuit: 2 gates
As a formula, one line per output:
OVEN = (TIMER AND NOT HEAT)
As a netlist, in the order you would wire it. Each g is one gate; the last line says which signal drives the output.
g1 = NOT HEATg2 = TIMER AND g1OVEN = g2
The search ran out of budget before it could rule out every smaller circuit, so 2 is the best anyone found, not a proof. If you build it in fewer, the leaderboard records it. Gates that do not feed an output are never counted.
Leaderboard for the day
Nobody posted a result on the day. The circuit above is the reference.