00015

力扣 02.07 链表相交

class Solution:
    def getIntersectionNode(self, headA: ListNode, headB: ListNode) -> ListNode:
        LA = 0
        LB = 0
        cur_a = headA
        while cur_a:
            LA += 1
            cur_a = cur_a.next
        cur_b = headB
        while cur_b:
            LB += 1
            cur_b = cur_b.next
        cur_a = headA
        cur_b = headB
        if LA - LB >= 0:
            for i in range(LA - LB):
                cur_a = cur_a.next
            for i in range(LB):
                if cur_a == cur_b:
                    return cur_a
                cur_a = cur_a.next
                cur_b = cur_b.next
        else:
            for i in range(LB - LA):
                cur_b = cur_b.next
            for i in range(LA):
                if cur_a == cur_b:
                    return cur_a
                cur_a = cur_a.next
                cur_b = cur_b.next
        return None