#pragma once
#include <iostream>
#include <string>

using namespace std;

template <typename T>
class Vector{
	unsigned sz;
	T* data;
public:
	Vector():sz(0),data(new T[0]){}
	Vector(Vector & v):sz(v.sz),data(new T[v.sz]){
		for(unsigned i=0; i<v.sz; ++i)
			data[i] = v.data[i];
	}
	Vector(unsigned s):sz(s),data(new T[s]){}
	Vector(unsigned s,T x):sz(s),data(new T[s]){
		for(unsigned i=0; i<s; ++i)
			data[i] = x;
	}
	~Vector(){delete[] data;}

	Vector & operator=(const Vector & v){
		if (&v!=this){
			sz = v.sz;
			data = new T[sz];
			for(unsigned i = 0; i < sz; ++i)
				data[i] = v.data[i];
		}
		return *this;
	}

	T* begin()const{
		return data;
	}

	T* end()const{
		return data+sz;
	}

	class Iterator{
		T* curr;
		friend Vector;
	public:
		Iterator():curr(0){}
		Iterator(const Vector & l):curr(l.begin()){}
		Iterator(T* n):curr(n){}
		Iterator(const Iterator & it): curr(it.curr){}
		Iterator & operator=(const Iterator & it){
			if (&it!=this){
				curr = it.curr;
			}
			return *this;
		}

		Iterator & operator++(){
			++curr;
			return *this;
		}
		Iterator & operator--(){
			--curr;
			return *this;
		}

		Iterator & operator+(int k){
			curr+=k;
			return *this;
		}

		Iterator & operator-(int k){
			curr-=k;
			return *this;
		}

		bool operator==(const Iterator & it)const{
			return curr==it.curr;
		}
		bool operator==(T* n)const{
			return curr==n;
		}
		bool operator!=(const Iterator & it)const{
			return curr!=it.curr;
		}
		bool operator!=(T* n)const{
			return curr!=n;
		}
		T & operator*()const{return *curr;}
		void operator*(T d){*curr = d}
		T* current()const{return curr;}
	};

	unsigned size()const{
		return sz;
	}

	bool empty()const{
		return sz;
	}

	T & operator[](unsigned i){
		if (i>=size || i<0){
			return NULL;
		}
		return data[i];
	}

	T operator[](unsigned i)const{
		if (i>=size || i<0){
			return NULL;
		}
		return data[i];
	}

	void push_back(T x){
		sz++;
		T* temp = new T[sz];
		for(unsigned i = 0; i < sz - 1; ++i)
			temp[i] = data[i];
		temp[sz-1] = x;
		delete data;
		data = temp;
	}

	void pop_back(){
		if (sz == 0){
			return NULL;
		}
		sz--;
		T* temp = new T[sz];
		for(unsigned i = 0; i < sz; ++i)
			temp[i] = data[i];
		delete data;
		data = temp;
	}

	void insert(unsigned pos, T x){
		if (pos<1 || pos>sz + 1){
			return NULL;
		}
		++sz;
		T* temp = new T[sz];
		for(unsigned i = 0; i<pos-1; ++i)
			temp[i] = data[i];
		temp[pos - 1] = x;
		for(unsigned i = pos; i < sz; ++i)
			temp[i] = data[i-1];
		delete data;
		data = temp;
	}

	void insert(Iterator it, T x){
		++sz;
		T* temp = new T[sz];
		unsigned pos = 0;
		for(Vector::Iterator i = begin(); i!=it; ++i){
			temp[pos] = data[pos];
			++pos;
		}
		temp[pos] = x;
		++pos;
		for(Vector::Iterator i = it+1; i!=end(); ++i){
			temp[pos] = data[pos-1];
			++pos;
		}
		delete data;
		data = temp;
	}

	void erase(unsigned pos){
		if (pos<1 || pos>sz){
			return NULL;
		}
		sz--;
		T* temp = new T[sz];
		for(unsigned i = 0; i<pos-1; ++i)
			temp[i] = data[i];
		for(unsigned i = pos-1; i < sz; ++i)
			temp[i] = data[i+1];
		delete data;
		data = temp;
	}

	void erase(Iterator it){
		sz--;
		T* temp = new T[sz];
		unsigned pos = 0;
		for(Vector::Iterator i = begin(); i!=it; ++i){
			temp[pos] = data[pos];
			++pos;
		}
		for(Vector::Iterator i = it+1; i != end()+1; ++i){
			temp[pos] = data[pos+1];
			++pos;
		}
		delete data;
		data = temp;
	}

	void erase(unsigned pos1, unsigned pos2){
		if (pos1<1 || pos1>sz || pos2<1 || pos2>sz || pos1>=pos2){
			return NULL;
		}
		sz -= pos2-pos1;
		T* temp = new T[sz];
		for(unsigned i = 0; i<pos1-1; ++i)
			temp[i] = data[i];
		for(unsigned i = pos1-1; i < sz; ++i)
			temp[i] = data[i + pos2-pos1];
		delete data;
		data = temp;
	}

	void erase(Iterator it1, Iterator it2){
		unsigned d = 0;
		for(Vector::Iterator i = it1; i != it2; ++i)
			++d;
		sz -= d;
		unsigned pos = 0;
		T* temp = new T[sz];
		for(Vector::Iterator i = begin(); i!=it1; ++i){
			temp[pos] = data[pos];
			++pos;
		}
		for(Vector::Iterator i = it2; i != end()+d; ++i){
			temp[pos] = data[pos+d];
			++pos;
		}
		delete data;
		data = temp;
	}

	void print(){
		for(unsigned i = 0; i < sz; ++i)
			cout << data[i] << ' ';
		cout << endl;
	}

};