js 获取list条数据

let list = [10, 20, 30, 40, 50];
console.log(list[2]); // 输出: 30

let list = [10, 20, 30, 40, 50];
for (let i = 0; i < list.length; i++) {
    console.log(list[i]);
}

let list = [10, 20, 30, 40, 50];
for (let item of list) {
    console.log(item);
}

let list = [10, 20, 30, 40, 50];
let doubled = list.map(x => x * 2);
console.log(doubled); // 输出: [20, 40, 60, 80, 100]

let list = [10, 20, 30, 40, 50];
let filtered = list.filter(x => x > 25);
console.log(filtered); // 输出: [30, 40, 50]

let list = [10, 20, 30, 40, 50];
let sum = list.reduce((accumulator, currentValue) => accumulator + currentValue, 0);
console.log(sum); // 输出: 150

let list = [10, 20, 30];
if (index >= 0 && index < list.length) {
    console.log(list[index]);
} else {
    console.log("Index out of bounds");
}

let list = [10, 20, 30];
let promises = list.map(async x => x * 2);
Promise.all(promises).then(results => console.log(results));