如何获得数组中的不同元素？

Question

让我们看一下我们有一个数组，该数组的元素的数目，类型和值未知。例如，我们有一个数组，预期结果是它包含200个“ a”元素，300个“ b”元素和500个“ c”元素。但是同样，我们不知道元素的值，数量，位置。使它们像上面的结果一样最简单的方法是什么？

Answer 1

请以最简单的方式使用简单的while循环删除重复项，并找到数组的唯一元素。

let alphaNumeric = ["a","a","a","a","a","a","a","a","a","a","b","b","b","b","b","b","b","b","c","c","c","c","c","c","c","c","1","1","1","1","1","a", "d","#","!", "p", "d", "d", "d", "d", "d"];
let i = 0;
let length = alphaNumeric.length;
let removeDuplicate = []; 
while(i < length) {
  if (!removeDuplicate.includes(alphaNumeric[i])){
    removeDuplicate.push(alphaNumeric[i]);
  }
  i += 1;
}
console.log(removeDuplicate);

希望，它会有所帮助。