Cyfa is a play on cypher, an old word for zero. Each day there are exactly five ways to make 0. Find them all, fast.

• Use 4 of the 6 numbers, each once at most, with 3 operators between them.
• Use every operator shown, as often as you like, and no others.
• Work strictly left to right: 2 + 3 × 4 is 20, not 14.
• Division must come out exact. Going below zero along the way is fine.
• Reach 0 only on the last step.
• Swaps that change nothing, like 2 + 3 and 3 + 2, count as the same answer.
• So does flipping every sign: 1 − 4 − 7 + 10 and 4 − 1 + 7 − 10 are one answer.

Example

Scoring

Your score is your time. The clock starts at your first tap and pauses when you leave or tap pause. A hint fills in the next step (an operator and the number after it) towards an answer you have not found, carrying on from what you have typed, and adds 30 seconds. A hint stays put: you can’t delete it or anything before it. Giving up reveals the rest and resets your streak.

This ends today's game and resets your streak to 0.