Round Robin Pairings

pair_round_robin.js

var players = ['A', 'B', 'C', 'D', 'E', 'F', 'G' ];

var generateRounds = function(players, bye){
	// add bye to rotation if number of players is odd
	if(players.length % 2 == 1){
	 players.push(bye);
	}

	// first player does not rotate
	var first = players.shift();

	// output
	var rounds = [];

	// create paired rounds
	for(var i = 0; i < players.length; i++){
		var currentPlayers = [].concat(first, players);
		var currrentRound = [];
		while(currentPlayers.length > 0){
			currrentRound.push([currentPlayers.shift(), currentPlayers.pop()]);
		}
		rounds.push(currrentRound);

		// rotate players
		players.push(players.shift())
	}

	return rounds;
}

generateRounds(players, 'BYE');