go
func getIntersectionNode(headA, headB *ListNode) *ListNode {
    if headA == nil || headB == nil {
        return nil
    }

    pA, pB := headA, headB

    for pA != pB {
        if pA == nil {
            pA = headB
        } else {
            pA = pA.Next
        }

        if pB == nil {
            pB = headA
        } else {
            pB = pB.Next
        }
    }
    return pA // 相交节点 or nil
}


// 测试代码
func main() {
    // 构造链表A: 1 -> 2 -> 3 \
    //                         6 -> 7
    //            4 -> 5     /
    // 链表B:          4 -> 5 /
    common := &ListNode{6, &ListNode{7, nil}}
    headA := &ListNode{1, &ListNode{2, &ListNode{3, common}}}
    headB := &ListNode{4, &ListNode{5, common}}

    intersection := getIntersectionNode(headA, headB)
    if intersection != nil {
        fmt.Printf("相交节点值: %d\n", intersection.Val)
    } else {
        fmt.Println("没有相交节点")
    }
}