【leetcode】【单链表】【19】Remove Nth Node From End of List

#include<iostream>
using namespace std;

struct ListNode {
int val;
ListNode *next;
ListNode(int x) : val(x), next(NULL) {}
};

class Solution {
public:
ListNode* removeNthFromEnd(ListNode* head, int n) {
int numOfNode = 0;
ListNode* cur = head;
while (cur){ //统计节点个数
++numOfNode;
cur = cur->next;
}
int beforeDelete = numOfNode - n;
ListNode* temp = NULL;
if (beforeDelete == 0){ //删除头结点情况
temp = head;
head = head->next;
}else{ //删除非头结点情况
cur = head;
while (--beforeDelete > 0)
cur = cur->next;
temp = cur->next;
cur->next = temp->next;
}
delete temp;
return head;
}
ListNode* createList(ListNode* head){
int numOfNode;
int value;
cout << "please input number of listNode:";
cin >> numOfNode;
cin >> value;
head = new ListNode(value);
ListNode* cur = head;
for (int i = 1; i < numOfNode; ++i){
cin >> value;
ListNode* temp = new ListNode(value);
cur->next = temp;
cur = temp;
}
return head;
}
void printNode(ListNode* head){
ListNode* cur = head;
while (cur){
cout << cur->val << " ";
cur = cur->next;
}
cout << endl;
}
};

int main(){
ListNode* head = NULL;
Solution lst;
head = lst.createList(head);
lst.printNode(head);

head = lst.removeNthFromEnd(head, 2);
lst.printNode(head);

system("pause");
return 0;
}