数组中sort slice pop

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             var add=【"2","3","4","5","6"】;      获取3,4，5       var getCenterValue=add.slice(1,add.length-1);var arr = [10, 20, 1, 2];arr.sort(function (x, y) {    if (x < y) {        return -1;    }    if (x > y) {        return 1;    }    return 0;}); // [1, 2, 10, 20]例如 ：var  a=["A","B","C","D","E","F","G"]   移除最后一个即：a.pop();