js求数组中全部数字可拼接出的最大整数示例代码

function insertSort(arr) {
 let res = [arr[0]];
 for (let i = 1, len = arr.length; i < len; i++) {
  let temp = arr[i];
  for (let j = i - 1; j >= 0; j--) {
   if (!compareNum(res[j],temp)) {
    res[j + 1] = res[j];
    res[j] = temp;
   } else {
    res[j + 1] = temp;
    break;
   }
  }
 }
 return res;
}
function compareNum(a,b) {
 a =""+a;
 b = ""+b;
 let aLen=a.length;
 let bLen=b.length;
 let aIndex=0;
 let bIndex=0;

 while (aIndex<aLen && bIndex<bLen){
  let flag=false;
  if (a[aIndex]==b[bIndex]){
   aIndex+1<aLen && (aIndex++,flag=true);
   bIndex+1<bLen && (bIndex++,flag=true);
  }else{
   break;
  }
  if (!flag){
   break;
  }
 }
 if (a[aIndex]>b[bIndex]){
  return true;
 }else{
  return false;
 }
}
let arr=[5,2,1,38];
// let arr=[5,2,1,38,52,4,5,593,8,55,555,492,493,7,9,61,66,6];
// let arr=[5,2,1,38,52,4,5,593,61,6];

function toInt(arr) {
 let newArr=insertSort(arr);
 document.write(newArr);
 return newArr.join("");
}

let intNum=toInt(arr);
console.log(intNum);