How to sum arrays in JavaScript

Methods for summing JavaScript arrays: 1. for loop, the code is [for (var i = 0; i

The operating environment of this tutorial: Windows 7 system, JavaScript version 1.8.5, DELL G3 computer.

Methods for summing JavaScript arrays:

1. for loop

    var sum = 0;
    console.time("for");
    for (var i = 0; i < arr.length; i++) {
        sum += arr[i];
    }
    console.timeEnd("for");
    console.log(sum);

2. while loop

    var sum = 0;
    function getSum(item, index, array) {
        sum += item;
    }
    console.time();
    arr.forEach(getSum);
    console.timeEnd();
    console.log(sum);

3. some method

    var sum = 0;
    function getSum(item, index, array) {
        sum += item;
    }
    console.time();
    arr.some(getSum);
    console.timeEnd();
    console.log(sum);

    var sum = 0;
    function getSum(item, index, array) {
        sum += item;
    }
    console.time();
    arr.map(getSum);
    console.timeEnd();
    console.log(sum);

    var sum = 0;
    function getSum(item, index, array) {
        sum += item;
    }
    console.time();
    arr.filter(getSum);
    console.timeEnd();
    console.log(sum);

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