lily's homework hackerrank solution in javascript

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Javascript program for lily's homework hacker rank solution

function swap(a, i, j) {

    let temp = a[i];

    a[i] = a[j];

    a[j] = temp;

}

function lilysHomework(a) {

    let noOfSwaps = 0, indexes = {};

    let sortedArray = a.slice().sort((a, b) => a - b);

    
    for (let i = 0; i < a.length; i++) {
        indexes[a[i]] = i;
    }

    for (let i = 0; i < a.length; i++) {

        if (sortedArray[i] != a[i]) {

            noOfSwaps++;

            let index = indexes[sortedArray[i]];

            indexes[a[i]] = index;

            swap(a, index, i);

        }

    }

    return noOfSwaps;

}

Time Complexity : O(n)

Space Complexity : O(n)