LeetCode 1013. 将数组分成和相等的三个部分 前端解法

/**
* @param {number[]} A
* @return {boolean}
 */
var canThreePartsEqualSum = function (A) {
    let sum = A.reduce((sum, ele) => {
        return sum + ele
    })
    let arr = 0
    let num = sum / 3
    if (sum % 3 === 0) {
        A.reduce((sum, ele) => {
            let count = 0
            if (sum + ele === num) {
                arr += 1
            } else {
                count = sum + ele
            }
            return count
        }, 0)
    }
    if (arr > 3 && num === 0) {
        arr = 3
    }
    return arr === 3
};