class Solution { public: ListNode* FindFirstCommonNode( ListNode* pHead1, ListNode* pHead2) { ListNode* cut1 = pHead1; ListNode* cut2 = pHead2; while(cut1 != cut2) { cut1 = cut1==nullptr ? pHead2 : cut1->next; cut2 = cut2==nullptr ? pHead1 : cut2->next; } return cut1; } };