Keno games on Ethereum operate through smart contracts, managing number selection mechanics for players. Unlike traditional lottery systems, where participants choose from limited options, keno allows participants to select multiple numbers from larger pools, typically ranging from 1 to 80. Selection logic determines valid pick quantities, payout calculations, and match verification processes. https://crypto.games/keno/ethereum implements these selection frameworks through contract functions that validate player choices, generate random draws, and calculate winnings based on match counts and bet sizes.
Player pick validation
Smart contracts enforce strict rules governing how many players select per game round. Minimum and maximum pick limits vary across implementations. Some platforms allow choosing between 1 and 10 numbers. Others permit selections up to 15 or 20 spots. The contract validates submitted picks against these boundaries before accepting bets. Duplicate number selections get rejected automatically. Players attempting to pick number 47 twice within a single game receive transaction failures. The validation logic checks array uniqueness before processing wagers. Sequential number requirements don’t typically exist. Players choose any combination within the valid range regardless of numerical order or patterns. Random selections work identically to deliberate pattern-based choices from the contract’s perspective.
Range boundary enforcement
Keno games define specific number ranges from which selections must come. The standard 1-80 range dominates most implementations, matching traditional keno formats. Some variations use 1-40 or 1-60 ranges for faster gameplay. Contract logic validates that every submitted number falls within defined boundaries. Attempting to select number 85 in an 80-number game triggers immediate rejection. Out-of-range submissions never reach the bet processing stage. This prevents invalid game states and ensures all picks exist within drawable number pools. Range definitions get hardcoded into contract deployment parameters. Operators choose ranges during initial setup and cannot modify them afterwards without deploying new contracts.
Payout matrix calculations
Match-based payouts follow predetermined matrices linking pick quantities to match counts and multiplier values. A player selecting 5 numbers who matches 3 receives different payouts than someone picking 10 numbers and matching 3. The mathematics behind these matrices balances expected returns against house edges. Higher pick quantities typically offer larger potential multipliers but require more matches for significant payouts:
- Single number picks pay 3-4x for matches
- Five spot selections yield 50-100x for all matches
- Ten spot games reach 1000-5000x for perfect matches
- Partial matches provide scaled returns based on difficulty
Contract storage holds complete payout matrices accessed during win calculation phases. The logic queries these tables using pick count and match count as indices. Returned multiplier values apply to original bet amounts, determining final prize transfers. Matrix structures remain static after deployment. Operators cannot adjust payout ratios mid-operation without contract upgrades.
Match verification process
After random number generation completes, contracts compare drawn numbers against player selections. The verification algorithm iterates through picked numbers, checking whether each appears in the drawn set. Match counters increment for every successful comparison. Smart contracts handle this through nested loops or mapping lookups, depending on implementation efficiency priorities. Efficient implementations use sorted arrays or hash maps, reducing comparison complexity. Less optimised contracts perform brute-force comparisons, accepting higher gas costs.
The verification produces match counts feeding directly into payout calculations. A player picking [12, 23, 34, 45, 56] against drawn numbers [12, 18, 23, 39, 45, 51, 62, 73, 78, 80] registers 3 matches. The contract then queries the payout matrix for “5 picks, 3 matches”, retrieving the appropriate multiplier. This deterministic process ensures identical inputs always produce consistent outputs, critical for blockchain transparency. Number selection logic in Ethereum-based keno establishes the fundamental mechanics determining valid player choices and subsequent payout calculations.
