linked list implementation

#include<iostream>
using namespace std;
class list{
    public:
        int data;
        list*next;
        list(int n){
            this->data=n;
            next=NULL;
        }
};
void print(list*tmp){
    while(tmp){
        cout<<tmp->data<<" ";
        tmp=tmp->next;
    }
    cout<<endl;
}

void push(list* &node,int n){
    list*tmp=new list(n);
    tmp->next=node;
    node=tmp;
}

void deletenode(list* &node,int x){
    if(!node)return;
    if(node->data==x){
        node=node->next;
        return;
    }
    list*tmp=node;
    while(tmp->next!=NULL && tmp->next->data != x){
        tmp=tmp->next;
    }
    if(tmp->next){
        tmp->next=tmp->next->next;
    }
}
void reverse(list* &node){
    if(!node || !node->next)return;
    list*curr=node,*prev=NULL;
    while(curr){
        list*next=curr->next;
        curr->next=prev;
        prev=curr;
        curr=next;
    }
    node=prev;
}
void middle(list* node){
    if(!node)cout<<-1<<endl;
    else if(!node->next)cout<<node->data<<endl;
    else{
        list*slow=node,*fast=node->next;
        while(fast && fast->next){
            slow=slow->next;
            fast=fast->next->next;
        }
        cout<<slow->data<<" ";
        if(fast)cout<<slow->next->data<<" ";
        cout<<endl;
    }
}
int main(){
    list*head=new list(0);
    head->next=new list(1);
    head->next->next=new list(2);
    push(head,3);
    push(head,4);
    push(head,5);
    push(head,6);
    print(head);
    deletenode(head,3);
    print(head);
    deletenode(head,0);
    print(head);
    deletenode(head,6);
    print(head);
    reverse(head);
    print(head);
    middle(head);
    push(head,7);
    print(head);
    middle(head);
}