Snake Arena

Two to four snakes share a board. Eat food to grow and refill your health; starve, hit a wall, or run into a body and you're out. Last snake alive wins.

Rules

Every turn all snakes move one cell at once. You choose a direction; you can't reverse onto your own neck.

Eating food grows you by one segment and resets your health to 100.

Health starts at 100 and drops by one every turn. Reach zero without eating and you starve out.

In a head-on collision, the strictly longer snake survives and the shorter one is eliminated. Equal lengths: both die.

You are eliminated by hitting a wall or any snake's body segment, including your own tail.

Food keeps respawning so the board is never empty for long. Outlast everyone to win; ties at the cap go to the longer snake.

Writing a bot

You see the whole board: every snake's body and health, all the food, and which snake is yours. Return a direction each turn.

The floor is "don't hit a wall or a body." The next rung is space: flood-fill the open area each safe move leads into so you don't trap yourself, and detour for food when your health runs low (that's what the Greedy bot does). Beyond that, control the center, cut off smaller snakes, and bait bigger ones into walls.

Input and output

Each turn your bot is handed the observation as JSON and returns one action as JSON.

Observation: { "you", "width", "height", "snakes", "food", "turn", "nonce" }. Each snake is { "body", "health", "dir", "alive" } with body head-first; food is a list of { "x", "y" }.

Action: { "dir": "up" | "down" | "left" | "right" }. Reversing onto your own neck is ignored (your snake keeps its heading).

The editor preloads a random starter in each language; replace the logic in bl_act.