how to compare values in array in javascript code example

Example 1: how to compare elements in an array

for (let i = 0; i < a.length; i++) {
    for (let k = i + 1; k < a.length; k++) {
        if (a[i] != a[k]) {
            //do stuff
        }
    }
}

Example 2: compare arrays javascript

// For regular 1D array
const array1 = [1,2,3,4]
const array2 = [1,2,3,4]

array1.join() === array2.join()
// '1,2,3,4' === '1,2,3,4'

// For anything more complex
const array3 = [1,2,3,[1,2,3]]
const array4 = [1,2,3,[1,2,3]]

JSON.stringify(array3) === JSON.stringify(array4)