#include <iostream>
 
struct Node{
	Node(): next(NULL){}
	Node *next;
	std::string data;
};
 
void printlist(Node* l){
	while(l){
		std::cout<<l->data<<std::endl;
		l = l->next;
	}
	std::cout<<"----"<<std::endl;
}
 
void reverse(Node*& l)
{
	Node* prev = NULL;
	while(l){
		auto next = l->next;
		l->next = prev;
		prev=l;
		l=next;
	}
	l = prev;
}
 
int main() {
	Node s,t,u,v;
	s.data = "1";
	t.data = "2";
	u.data = "3";
	v.data = "4";
	s.next = &t;
	t.next = &u;
	u.next = &v;
	Node* ptr = &s;
	printlist(ptr);
    reverse(ptr);
    printlist(ptr);
	return 0;
}
 

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