编辑代码

function unique(arr) {
    let newArr = [];
    for (let i = 0; i < arr.length; i++) {
        if (newArr.indexOf(arr[i]) === -1) {
            newArr.push(arr[i]);
        }
    }
    return newArr;
}
let re = unique(['c','a','b','a','z','x','c','b']);
console.log(re);