/* struct ListNode { int val; struct ListNode *next; ListNode(int x) : val(x), next(NULL) { } };*/ class Solution { public: ListNode* FindFirstCommonNode( ListNode* pHead1, ListNode* pHead2) { ListNode* p1 = pHead1; ListNode* p2 = pHead2; if(p1 == nullptr || p2 == nullp...