My Goal: Each player has an option to place a bet, and for each player the winning chance of their bet would be calculated and displayed on the web page. So as an example if player 1 bets 5000 credits and the total pot is 15000 credits, player 1 has a 33% chance to win. After this calculation I would like to pick a winner from all the players that placed a bet.
Example game:
Total amount : 15000 credits.
player 1 : 3000 credits -> 20% of winning
player 2 : 1500 credits -> 10% of winning
player 3 : 7500 credits -> 50% of winning
player 4 : 1200 credits -> 8% of winning
Player 5 : 1800 credits -> 12% of winning
How should I approach the way of picking a random winner from all the players? I was thinking of generating one random number and comparing it to the win chance somehow. Any tips?
Percentage does not always work due to rounding errors. For instance betting 1 when the total pot is 1000 yields 0% chance.
I recommend drawing a random number in range [0,tototalAmount)
// player 1 bets 1500, player 2 bets 2300, player 3 bets 4000
let bets = [1500,2300,4000];
bets.forEach((e,i)=>bets[i]=(i==0)?e:e+bets[i-1]);
//now bets is [1500,3800,7800]
console.log(bets);
let maxDraw = bets[bets.length-1];
//Draw
let drawnNumber = Math.floor( Math.random() * (maxDraw) );
// drawnNumber is in range 0~7799
//so if the drawn number is in ranges:
// 0~1499 : player 1 wins. odds are 1500/7800
// 1500~3799 : player 2 wins 2300/7800
// 3800 7799 : player 3 wins 4000/7800
console.log("drawn number =",drawnNumber);
// remember the above are checked in order.
let winner = 0;
bets.forEach((e,i)=>{
if(!winner && drawnNumber<=bets[i])
winner = i+1;
});
console.log("player",winner,"wins");This keeps rates 100% proportional.