问题描述
我有玩家列表,想用 JavaScript 为国际象棋锦标赛创建一个循环生成器。 循环赛应该如下图所示,分别为 10 支球队和 6 支球队:
我尝试为偶数和奇数创建单独的逻辑,但我没有找到最好的算法:
var list = [1,2,3,4,5,6,7,8,9,10];
var pairing = []
var size = list.length;
var halfSize = size/2;
var evenorOdd
if (halfSize % 2 != 1) {
list.push("BYE")
}
for (var i=0 ; i <= size-1 ; i++) {
var lastOne = list[size]
if (isEven(i)) {
var games = []
for (var j = 0; j <= halfSize-1; j++) {
if (j == 0) {
games.push({"home": list[size-1],"away": list[(i+2)/2-1+j]})
} else {
if(list[size-j-i/2]==list[size-2] && i>0){
games.push({"home": list[j+i/2],"away": list[0]})
} else {
games.push({"home": list[j+i/2],"away": list[(i+2)/2]})
}
}
}
pairing.push({"round":i+1,"games":games})
} else {
}
}
console.log(pairing)
function isEven(num) {
if (num % 2 == 0)
return true;
return false;
}
我得到的结果不像上图中的配对,它只正确产生了第一轮。
还有一些其他类似的问题有答案,例如 Scheduling algorithm for a round-robin tournament?,但它们是针对足球比赛的,我希望针对国际象棋比赛:它与足球相比有一些差异。
如何更正我的国际象棋锦标赛生成器,使其适用于任意数量的玩家?
解决方法
您可以使用余数运算符 (%
) 来使用模块化逻辑,因为显然一个数字增加,而另一个数字减少。第一场比赛是一个例外,最后一个玩家总是参与其中,并且增加的计数器与之前生成的对相同。它还可以根据回合的平价交换双方。
这是一种使用 map
和 Array.from
调用动态创建数组的方法。递增和递减变量在用作索引时更新:
function generatePairings(players) {
let n = players.length;
let mod = n - 1;
let decr = 0;
let incr = -1;
let arr = {length: n / 2 - 1}; // n is assumed to be even
let props = ["away","home"];
let template = { home: players[mod],away: players[mod] };
return players.slice(1).map((_,i) => ({
round: i + 1,games: [
{ ...template,...{ [props[i % 2]]: players[incr = (incr + 1) % mod] }},...Array.from(arr,() => ({
home: players[incr = (incr + 1) % mod],away: players[decr = (decr + mod - 1) % mod]
}))
]
}));
}
console.log(generatePairings([1,2,3,4,5,6]));
或者使用 for
循环:
function generatePairings(players) {
let n = players.length;
let mod = n - 1;
let decr = 0;
let incr = -1;
let gameCount = n / 2; // n is assumed to be even
let props = ["away",away: players[mod] };
let pairings = [];
for (let round = 1; round < n; round++) {
let games = [{ ...template,...{ [props[round % 2]]: players[incr = (incr + 1) % mod] }
}];
for (let k = 1; k < gameCount; k++) {
games.push({
home: players[incr = (incr + 1) % mod],away: players[decr = (decr + mod - 1) % mod]
});
}
pairings.push({ round,games });
}
return pairings;
}
console.log(generatePairings([1,6]));