Description

Submission

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:
    ListNode *getIntersectionNode(ListNode *headA, ListNode *headB) {
        if(headA == nullptr || headB == nullptr) return nullptr;
        ListNode* pA = headA, *pB = headB;
        
        while(pA != pB) {
            pA = pA ? pA->next : headB;
            pB = pB ? pB->next : headA;
        }

        return pA;
    }
};