面试题 02.07. 链表相交 - 力扣（Leetcode）
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public class IntersectionOfTwoLinkedListsLcci02_07 {
public static void main(String[] args){
ListNode headA = initLinkedList(new int[]{3,9,8,7});
ListNode headB = initLinkedList(new int[]{11,5,4,4});
ListNode temp = initLinkedList(new int[]{3,2,1,3});
ListNode cur = headA;
while(cur.next != null){
cur = cur.next;
}
cur.next = temp;
printLinkedList(new Solution().getIntersectionNode(headB,headA));
}
public static ListNode initLinkedList(int[] nums){
ListNode head = new ListNode(nums[0]);
ListNode cur = head,node;
for(int i = 1; i < nums.length; i++){
node = new ListNode(nums[i]);
cur.next = node;
cur = node;
}
return head;
}
public static void printLinkedList(ListNode head){
System.out.println();
ListNode cur = head;
while(cur != null){
System.out.print(cur.val + "->");
cur = cur.next;
}
System.out.println();
}
}
class Solution {
public ListNode getIntersectionNode(ListNode headA, ListNode headB) {
ListNode curA = headA;
ListNode curB = headB;
int lenA = 0,lenB = 0;
while (curA != null){
curA = curA.next;
lenA++;
}
while (curB != null){
curB = curB.next;
lenB++;
}
curA = headA;
curB = headB;
if (lenA < lenB) {
int temp = lenA;
lenA = lenB;
lenB = temp;
ListNode tempNode = curA;
curA = curB;
curB = tempNode;
}
int gap = lenA - lenB;
while(gap-- > 0){
curA = curA.next;
}
while (curA != null){
if (curA == curB) {
return curA;
}
curA = curA.next;
curB = curB.next;
}
return null;
}
}
class ListNode {
int val;
ListNode next;
public ListNode (){}
public ListNode (int val){
this.val = val;
}
public ListNode (int val, ListNode next){
this.val = val;
this.next = next;
}
}
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反思：
3，11，5，4，3
11，5，4，9
会返回11
实际上：
