92. Reverse Linked List II

#include<iostream>
#include <cstdio>
using namespace std;
struct ListNode {
int val;
ListNode *next;
ListNode(int x) : val(x), next(NULL) {}
};
ListNode* createList(int a[],int n){

ListNode* head=NULL,*rear;
for(int i=0;i<n;i++){
ListNode* temp=new  ListNode(a[i]);
if(head==NULL){
head=temp;
rear=head;
}else{
rear->next=temp;
rear=rear->next;
}
}
return head;
}
void printList(ListNode* head){
ListNode* pos=head;
while(pos){
cout<<pos->val<<" ";
pos=pos->next;
}
}
ListNode* reverseBetween(ListNode* head, int m, int n) {
ListNode* pos=head;
ListNode* mpos,*npos;
int count=0,i=0,flag=0;
int num[10000];
while(pos){
count++;
if(flag==1){
num[i++]=pos->val;
}
if(count==m)
{
mpos=pos;
num[i++]=pos->val;
flag=1;
}
if(count==n)
{
npos=pos;
break;
}
pos=pos->next;
}
pos=mpos;
while(pos!=npos->next){
pos->val=num[--i];
pos=pos->next;
}
return head;
}

int main(int argc,char *argv[])
{
int v[5]={1,2,3,4,5};
ListNode* p=createList(v,5);
printList(reverseBetween(p,2,4));
return 0;
}