题解 | 两个链表的第一个公共结点

/**
 * class ListNode(var `val`: Int) {
 *     var next: ListNode? = null
 * }
 */
object Solution {
    /**
    * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
    *
    * 
        * @param pHead1 ListNode类 
        * @param pHead2 ListNode类 
        * @return ListNode类
    */
    fun FindFirstCommonNode(pHead1: ListNode?,pHead2: ListNode?): ListNode?  {
        // write code here
        var n1:ListNode? = pHead1
        var n2:ListNode? = pHead2
        while(n1!=n2){
            n1 = if(n1==null) pHead2 else n1.next
            n2 = if(n2 == null) pHead1 else n2.next
        }
        return n1
    }
}