add: 只出现一次的数字等

src/list/merge-k-sorted-lists.js

@@ -0,0 +1,64 @@
+/**
+ * 合并俩链表
+ * @param {ListNode[]} left
+ * @param {ListNode[]} right
+ */
+export const merge = (left, right) => {
+  const head = {}
+  let current = head
+  while (left !== null && right !== null) {
+    if (left.val < right.val) {
+      if (left.val !== null) {
+        current.next = left
+        current = current.next
+      }
+      left = left.next
+    } else {
+      if (right.val !== null) {
+        current.next = right
+        current = current.next
+      }
+      right = right.next
+    }
+  }
+
+  if (left === null) {
+    current.next = right
+  } else {
+    current.next = left
+  }
+
+  return head.next
+}
+
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val) {
+ *     this.val = val;
+ *     this.next = null;
+ * }
+ */
+/**
+ * @param {ListNode[]} lists
+ * @return {ListNode}
+ */
+export const mergeKLists = function (lists) {
+  if (lists.length === 0) return null
+  if (lists.length === 1) return lists[0]
+  if (lists.length === 2) return merge(lists[0], lists[1])
+
+  // 归并排序，见 src/array/reverse-pairs.js
+  const mid = lists.length >> 1
+
+  const left = []
+  for (let n = 0; n < mid; n++) {
+    left[n] = lists[n]
+  }
+
+  const right = []
+  for (let n = 0, i = mid; i < lists.length; n++, i++) {
+    right[n] = lists[i]
+  }
+
+  return merge(mergeKLists(left), mergeKLists(right))
+}