v2ex盲盒概率

gistfile1.js

function permutation(a, callback, m) {
  let n = a.length;
  m = m || n;
  function recur(_a, tmpResult = []) {
    if (tmpResult.length === m) {
      callback(tmpResult);
    } else {
      for (let i = 0; i < _a.length; i++) {
        let tmpA = _a.concat();
        let _tmpResult = tmpResult.concat();
        _tmpResult.push(tmpA[i]);
        tmpA.splice(i, 1);
        recur(tmpA, _tmpResult);
      }
    }
  }
  recur(a);
}

var artObjects = ["女孩", "男孩", "乳牛", "博客", "甜点", "朋克"]

var impossibleObjects = [
  ["甜点", "朋克", "女孩"],
  ["乳牛", "甜点", "博客"],
  ["女孩", "乳牛", "甜点"],
  ["甜点", "乳牛", "男孩"],
  ["博客", "女孩", "男孩"],
  ["朋克", "男孩", "博客"]
]

var count = {}
artObjects.forEach(x => count[x] = artObjects.map(y => 0))
permutation(artObjects, (tmpResult) => {
  if (impossibleObjects.every((x, i) => !x.includes(tmpResult[i]))) {
    tmpResult.forEach((x, i) => {
      count[x][i] += 1
    })
  }
})
artObjects.forEach(name => {
  const sum = count[name].reduce((a, b) => a + b, 0);
  console.log(name, ':', count[name].map(num => Math.round(num * 100 / sum)))
})