function ListNode(x) {
 this.val = x
 this.next = null
}

export function Merge1(pHead1, pHead2) {
 // 单调不减 可以理解 等于或者大于递增
 let p1 = pHead1
 let p2 = pHead2
 const result = {}
 // 保留头指针
 const kk = result
 while (p1 !== null && p2 !== null) {
 // console.log(p1,p2)
 if (p1.val <= p2.val) {
 // 左边小
 kk.next = p1
 p1 = p1.next
 }
 else {
 kk.next = p2
 p2 = p2.next
 }
 console.log(p1, p2)
 }

 console.log('test:', result, kk)

 console.log('go:', p1, p2)
 console.log('go1:', pHead1, pHead2)
 if (p1) {
 kk.next = p1
 }
 if (p2) {
 kk.next = p2
 }
 console.log(kk)
 return result.next
}

export function Merge(pHead1, pHead2) {
 const vHead = {}
 let cur = vHead
 while (pHead1 && pHead2) {
 if (pHead1.val <= pHead2.val) {
 cur.next = pHead1
 pHead1 = pHead1.next
 }
 else {
 cur.next = pHead2
 pHead2 = pHead2.next
 }
 cur = cur.next
 }
 cur.next = pHead1 || pHead2
 return vHead.next
}

const pre = new ListNode(1)
pre.next = new ListNode(3)
pre.next.next = new ListNode(5)
console.log('pre:', pre)

const last = new ListNode(2)
last.next = new ListNode(4)
last.next.next = new ListNode(6)
console.log('last:', last)
console.log(Merge(pre, last))
console.log(Merge1(pre, last))