JS创建一个数组1.求和 2.求平均值 3.最大值 4.最小值 5.数组逆序 6.数组去重 0.退出

rs = require("readline-sync");

let arr = [];

console.log("请输入数组的长度：");

let arr_length = rs.question() - 0;

console.log("请添加数组中的元素：");

for (let index = 0; index < arr_length; index++) {

    arr[index] = rs.question() - 0;

}

console.log("创建的数组为：");

console.log(arr);

console.log("请对数组选择操作：1.求和 2.求平均值 3.最大值 4.最小值 5.数组逆序 6.数组去重 0.退出");

let option = rs.question() - 0;

let sum = 0,  arr_max = arr[0], arr_min = arr[0];

arr.forEach(element => {

    sum += element;

});

switch (option) {

    case 1:

        console.log(sum);

        break;

    case 2:

        console.log(sum / arr.length);

        break;

    case 3:

    for (let index = 1; index < arr.length; index++) {

        if (arr_max < arr[index]) {

            arr_max = arr[index];

        }

    }

        // for (let index = 1; index < arr.length - 1; index++) {

        //     arr_max = arr[index + 1] = Math.max(arr[index], arr[index + 1]);

        // }

        console.log(arr_max);

        break;

    case 4:

    for (let index = 1; index < arr.length; index++) {

        if (arr_min > arr[index]) {

            arr_min = arr[index];

        }

    }

        // for (let index = 1; index < arr.length - 1; index++) {

        //     arr_min = arr[index + 1] = Math.min(arr[index], arr[index + 1]);

        // }

        console.log(arr_min);

        break;

    case 5:

        arr.reverse();

        // for (let index = 0; index <arr.length/2; index++) {

        //     let t=arr[index];

        //     arr[index]=arr[arr.length-1-index];

        //     arr[arr.length-1-index]=t;

        //  }

        console.log(arr);

        break;

    case 6:

        let arr_new = new Set(arr);

        // let arr_new = [], index_new = 0;

        //    for (let i = 0; i < arr.length-1; i++) {

        //       for (let j = i+1; j < arr.length; j++) {

        //          if (arr[i]==arr[j]) {

        //         delete arr[i];

        //          }

        //       }

        //    }

        //    arr.forEach(element => {

        //        if (typeof element=="number") {

        //            arr_new[index_new]=element;

        //            index_new++;

        //        }

        //    });

        console.log(arr_new);

        break;

    case 0:

        break;

    default:

        console.log("输入有误，程序结束");

        break;

}

console.log(1+undefined)