题解 | #牛群的合并#

/*
 * function ListNode(x){
 *   this.val = x;
 *   this.next = null;
 * }
 */
/**
 * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
 *
 * 
 * @param lists ListNode类一维数组 
 * @return ListNode类
 */
function mergeKLists(lists) {
    if(lists.length === 0){
        return null
    }

    // write code here
    let merge = (l1, l2) => {
        let dummy = new ListNode(-1)
        let curr = dummy

        while (l1 && l2) {
            if (l1.val < l2.val) {
                curr.next = l1
                l1 = l1.next
            } else {
                curr.next = l2
                l2 = l2.next
            }
            curr = curr.next
        }

        while (l1) {
            curr.next = l1
            l1 = l1.next
            curr = curr.next
        }

        while (l2) {
            curr.next = l2
            l2 = l2.next
            curr = curr.next
        }

        return dummy.next
    }

    let res = lists.reduce((a, b) => merge(a, b))
    return res
}


module.exports = {
    mergeKLists: mergeKLists
};