//reduce数组去重
let arr = [1,2,3,4,5,2,3]
let res=arr.reduce((pre,cur)=>{
    if(!pre.includes(cur)){
        pre.push(cur)
    }
    return pre
},[])
console.log(res)
//reduce数组去重
let newArr = Array.from(new Set(arr));
console.log(newArr);
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