JavaScript array deduplication solution

let arr = [12,1,12,3,1,88,66,9,66];
function unique(ary) {
        let s = new Set(ary);
        // Array.from: Convert the set data structure into a real array;
        return Array.from(s)
    }
    unique(arr);

let arr = [12,1,12,3,1,88,66,9,66];
function unique(ary) {
        let obj = {};
        for(let i=0;i<ary.length;i++){
            let cur = ary[i];
            if (obj[cur]) {
                //ary.splice(i,1);// causes the array to collapse ary[i]=ary[ary.length-1];
                ary.length--; // delete the last item i--;
                continue;
            }
            obj[cur]=cur; // Add a key-value pair to obj; the attribute name and attribute value are the same}
    }
    unique(arr);

let arr = [12,1,12,3,1,88,66,9,66];
 function unique(ary) {
        let newAry = [];
        for(let i=0;i<ary.length;i++){
            let cur = ary[i];
            if (newAry.indexOf(cur)===-1){
                newAry.push(cur);
            }
        }
        return newAry;
    }
    unique(arr)

let arr = [12,1,12,3,1,88,66,9,66];
function unique(ary) {
       let a = ary.sort(function (a,b) {
           return ab;
       });
       for(let i=0;i<a.length;i++){
           if(a[i]===a[i+1]){
               a.splice(i+1,1);
               i--;
           }
       }
       return a;
   }
   unique(arr)

let arr = [12,1,12,3,1,88,66,9,66];
function unique(ary) {
        let newAry = [];
        let len ​​= ary.length;
        for(let i=0;i<len;i++){
            let cur = ary[i];
            if (!newAry.includes(cur)){
                newAry.push(cur);
            }
        }
        return newAry;
    }
    console.log(unique(arr));

let arr = [12,1,12,3,1,88,66,9,66];
function unique(ary) {
        let obj = {};
        return ary.filter(function (item,index,a) {
            // item: each member of the array // index: the index corresponding to the member // a: the entire array // hasOwnProperty is used to check whether the property has appeared;
           return obj.hasOwnProperty(typeof item+item)?false:obj[typeof item+item]=true;
           if (obj.hasOwnProperty(typeof item+item)){
               return false
           }else{
               obj[typeof item+item]=true;
               return true;
           }
        })
    }
    console.log(unique(arr))

let arr = [12,1,12,3,1,88,66,9,66];
    function unique(ary) {
        return ary.filter(function (item,index,a) {
            return ary.indexOf(item)===index;
        })
    }
    console.log(unique(arr));

let arr = [12,1,12,3,1,88,66,9,66];
 function unique(ary) {
        for(let i=0;i<ary.length;i++){
            for(j=i+1;j<ary.length;j++){
                if(ary[i]===ary[j]){
                    ary.splice(j,1);
                    j--;
                }
            }
        }
        return ary;
    }
    unique(arr);

let arr = [12,1,12,3,1,88,66,9,66];
function unique(ary) {
        let len ​​= ary.length;
        ary = ary.sort(function (a,b) {
            return ab;
        });
        function loop(index) {
            if(index>=1){
                if(ary[index]===ary[index-1]){
                    ary.splice(index,1);
                }
                loop(index-1)
            }
        }
        loop(len-1);
        return ary;
    }
    console.log(unique(arr));

let arr = [12,1,12,3,1,88,66,9,66];
function unique(ary) {
        let newAry = [];
        let map = new Map();
        for(let i=0;i<ary.length;i++){
            if (!map.has(ary[i])){
                map.set(ary[i],true);
                newAry.push(ary[i]);
            }
        }
    }
    unique(arr);

let arr = [12,1,12,3,1,88,66,9,66];
function unique(ary) {
        // reduce: The first one is a function, and the second parameter will be passed to prev of the first callback;
        return ary.reduce((prev,next)=>{
            //The return value of this function is prev for the next execution;
            return prev.includes(next)?prev:[...prev,next];
        },[])
    }
    console.log(unique(arr));

let arr = [12,1,12,3,1,88,66,9,66];
    let a = [...new Set(arr)];
    console.log(a);