LeetCode 3131. Find the Integer Added to Array I

/**
 * @param {number[]} nums1
 * @param {number[]} nums2
 * @return {number}
 */
var addedInteger = function (nums1, nums2) {
    if (nums1.length < 1 || nums2.length > 100 || nums1.length !== nums2.length) {
        return 0
    }

    const sum = (p, c) => p + c

    const sum1 = nums1.reduce(sum)
    const sum2 = nums2.reduce(sum)
    const total = sum2 > sum1 ? sum2 - sum1 : -(sum1 - sum2)

    return (total % nums1.length) === 0 ? total / nums1.length : 0
};