Question

window.onload = start;

function start () {
  var name = ["Hans","Ole","Nils","Olav","Per","Knut","Kari","Line","Pia"]
  var random = Math.floor(Math.random()*8)
  var random2 = Math.floor(Math.random()*8)
  var random3 = Math.floor(Math.random()*8)
  var name2 = []
  name2.push(name[random])
  name2.push(name[random2])
  name2.push(name[random3])

  for(i=0; i<3; i++) {
  document.getElementById("par").innerHTML += name2[i] + "<br/>" ;
  }
}

到目前为止，使用此代码，我可以从名称数组中生成3个随机名称。但我希望这三个名字不要重复，我不知道如何实现这一点。

Answer 1

我创建了一个使用递归的解决方案。

函数 randomNames 重复三次。每次调用count都会增加，而名称是一个没有已经采用的名称的数组。它返回一个包含三个随机名称的数组。

function start () {
  var name = ["Hans","Ole","Nils","Olav","Per","Knut","Kari","Line","Pia"]

  function randomNames(count, names) {
    if(count >= 3) return [];
    var random = Math.floor(Math.random()*(names.length-1));
    // remove current name
    var name = names.splice(random, 1);
    return randomNames(++count, names).concat(name);
  }

  var random = randomNames(0, name);
}

Answer 2

您可以对所选项目使用哈希表，并进行检查，直到找到所有需要的项目。

window.onload = start;

function start() {
    var name = ["Hans", "Ole", "Nils", "Olav", "Per", "Knut", "Kari", "Line", "Pia"],
        hash = {},
        random;

    while (Object.keys(hash).length < 3) {
        do {
            random = Math.floor(Math.random() * name.length);
        } while (hash[random])
        hash[random] = true;
        document.getElementById("par").innerHTML += name[random] + "<br/>";
    }
}

<div id="par"></div>

ES6与Set

window.onload = start;

function start() {
    var name = ["Hans", "Ole", "Nils", "Olav", "Per", "Knut", "Kari", "Line", "Pia"],
        hash = new Set,
        random;

    while (hash.size < 3) {
        do {
            random = Math.floor(Math.random() * name.length);
        } while (hash.has(random))
        hash.add(random);
        document.getElementById("par").innerHTML += name[random] + "<br/>";
    }
}

<div id="par"></div>

Answer 3

将random2和random 3的赋值替换为：

var random = Math.floor(Math.random()*8);
var random2, random3;
do { 
  random2 = Math.floor(Math.random()*8);
  } while (random2==random);

do {
  random3 = Math.floor(Math.random()*8);
  } while (random3==random || random3==random2);

在此处试试：https://jsfiddle.net/o04tf9ct/

Answer 4

也许这可能会有所帮助。我随机化了数组的顺序，然后选择前三个元素。这允许零重复名称并在每次运行函数时生成新的答案。不确定你的HTML是什么样的，所以我只是添加了id＆＃34; demo＆＃34;。

var players = ["Hans","Ole","Nils","Olav","Per","Knut","Kari","Line","Pia"];



function tournament() {
  var names = [];
  players.sort(function(a,b){return 0.5 - Math.random()});
  for (i=0; i<3; i++){
    names.push(players[i]);
  }
  document.getElementById("demo").innerHTML = names;
}

function tournament() { var names = []; players.sort(function(a,b){return 0.5 - Math.random()}); for (i=0; i<3; i++){ names.push(players[i]); } document.getElementById("demo").innerHTML = names; }

如何重复生成3个没有相同名称的名称

4 个答案: