问需要帮助获得尽可能多的独特啤酒

EN

let Beers = [ 
    {id: 1, size: 4},
    {id: 5, size: 1},
    {id: 10, size: 0.5},
    {id: 11, size: 1},
    {id: 12, size: 2},
    {id: 13, size: 1},
];

let TrunkSize = 2;

AllCombinations = [];
var combStrings = []
function GetCombinations(currentCombination, beers, remainingSum) 
{ 

    if (remainingSum < 0) 
        return;// Sum is too large; terminate recursion

    else {
        if (currentCombination.length > 0) 
        {
            currentCombination.sort((a,b)=>{
              return a.id > b.id
            });  
            //var uniquePermutation = true;

            var tmp = currentCombination.map((cc)=>{
                  return cc.id;
               })

            if (combStrings.indexOf(JSON.stringify(tmp)) == -1) {
                this.AllCombinations.push(currentCombination);
                var tmp = currentCombination.map((cc)=>{
                  return cc.id;
                })
                combStrings.push(JSON.stringify(tmp))
            }
        }
    }

    for (var i = 0; i < beers.length; i++) {
        var newChoices = beers.slice();       
        var newCombination = currentCombination.concat(newChoices.splice(i, 1)); 
        var newRemainingSum = remainingSum - beers[i].size;
        this.GetCombinations(newCombination, newChoices, newRemainingSum);
    }
}
GetCombinations([],Beers,TrunkSize)
console.log(AllCombinations,combStrings)

let Beers = [ 
            {id: 1, size: 4},
            {id: 5, size: 1},
            {id: 10, size: 0.5},
            {id: 11, size: 1},
            {id: 12, size: 2},
            {id: 13, size: 1},
];

let TrunkSize = 2;

// get all combinations (stolen from http://stackoverflow.com/questions/5752002/find-all-possible-subset-combos-in-an-array )
function combinations(array) {
    return new Array(1 << array.length).fill().map(
        (e1,i) => array.filter((e2, j) => i & 1 << j));
}

// filter them out if the summed sizes are > trunksize
var valids = combinations(Beers).filter(function(el) {
  return el.reduce(function(a,b){return a+b.size;}, 0) <= TrunkSize;
});

console.log(valids);

000000
000001
000010
000011
000100
000101
000110
000111

...

111111

function getCombination(beers, trunkSize) {
  const beersCount = beers.length;
  const combinationsCount = Math.pow(2, beersCount);
  
  const combinations = [];
  
  let i = 0; // Change this to 1 to remove the empty combination that will always be there.
  
  while(i < combinationsCount) {
    const binary = i.toString(2);
    const bits = Array.prototype.concat.apply(Array(beersCount - binary.length).fill(0), binary.split('').map(parseInt));
    
    const combination = [];
    
    let bit = 0;
    let total = 0;
    
    while(bit < beersCount && total <= trunkSize) {
      if (bits[bit]) {
        const beer = beers[bit];

        total += beer.size;
      
        combination.push(beer);
      }
      
      ++bit;
    }
    
    if (total <= trunkSize) {
      combinations.push(combination)
    }
  
    ++i;
  }
  
  return combinations;
}

const combinations = getCombination([ 
  {id: 1, size: 4},
  {id: 5, size: 1},
  {id: 10, size: 0.5},
  {id: 11, size: 1},
  {id: 12, size: 2},
  {id: 13, size: 1},
], 2);

console.log(JSON.stringify(combinations, null, 2));