【leetcode】86.分隔链表

86.分隔链表

/**  
 * Definition for singly-linked list.  
 * class ListNode {  
 *     val: number  
 *     next: ListNode | null  
 *     constructor(val?: number, next?: ListNode | null) {  
 *         this.val = (val===undefined ? 0 : val)  
 *         this.next = (next===undefined ? null : next)  
 *     }  
 * }  
 */
 
function partition(head: ListNode | null, x: number): ListNode | null {  
  let small = new ListNode(-1),  
    smallP = small,  
    large = new ListNode(-1),  
    largeP = large;
 
  while (head) {  
    if (head.val < x) {  
      smallP.next = {  
        val: head.val,  
        next: null,  
      };  
      smallP = smallP.next;  
    } else {  
      largeP.next = {  
        val: head.val,  
        next: null,  
      };  
      largeP = largeP.next;  
    }  
    head = head.next;  
  }  
  largeP.next = null;  
  smallP.next = large.next;  
  return small.next;  
}

可以看出内存还有很大的优化空间