pls spag

#include <iostream>
#include <vector>
#include <list>
#include <iterator>
#include <algorithm>

using namespace std;

// Define functions even, odd, lt10, gt10, alwaystrue
// All these functions returns bool and have one int parameter
// Meanings are obvious

bool even(int n) {return n%2==0;}
bool odd(int n) {return n%2!=0;}
bool lt10(int n) {return n>10;}
bool gt10(int n) {return n<10;}
bool alwaystrue(int n) {return true;}



void main()
    {
    int tab[] = { 2, 5, 8, 3, 12, 15, 17, 23, 3, 26, 30, 5, 18, 22, 1 };
    for (int i:tab)
        cout << i << "," ;
    cout<<endl<<endl;

    vector<int> v, v_even, v_odd;
    back_insert_iterator<vector<int>> iitv(v);
	//auto iitv = back_inserter(v);

    // Define back inserters for vectors v_even and v_odd
	auto iitve = back_inserter(v_even);
	back_insert_iterator<vector<int>> iitvo(v_odd);

    copy(tab, tab+sizeof(tab)/sizeof(int), iitv);
    for (int i:v)
        cout << i << "," ;
    cout<<endl<<endl;

    // Fill vector v_even with proper elements of vevtor v,
    // use copy_if algorithm and even function
    // List v_even elements to screen

	copy_if(v.begin(), v.back(), iitve, even);
	for(int i:v_even)
		cout<< i <<",";



    // Fill vector v_odd with proper elements of vevtor v,
    // use copy_if algorithm and odd function
    // List v_odd elements to screen

	copy_if(v.begin(), v.back(), iitvo, odd);
	for(int i: v_odd)
		cout<<i<<",";


    cout << count_if(v.begin(),v.end(),lt10) << endl << endl ;
    cout << count_if(v.begin(),v.end(),gt10) << endl << endl ;
    cout << count_if(v.begin(),v.end(),alwaystrue) << endl << endl ;

    // Find max and min element of v vector
    // use proper algorithms

	cout<<"Max element of vector v: "<<*max_element(v.begin(), v.back() )<<endl;
	cout<<"Min element of vector v: "<<*min_element(v.begin(), v.back() )<<endl;

    vector<int> v1(v);
    vector<int> v2(v);

 /*   auto it=v1.begin();
    while ( it!=v1.end() )
        if ( even(*it) )
            it=v1.erase(it);
        else
            ++it;
    for (int i:v1)
        cout << i << "," ;
    cout<<endl<<endl;

    auto itr = remove_if(v2.begin(),v2.end(),even);
    for (int i:v2)
        cout << i << "," ;
    cout<<endl<<endl;

    v2.erase(itr,v2.end());
    for (int i:v2)
        cout << i << "," ;
    cout<<endl<<endl;*/

    // Sieve of Eratosthenes
    // Find all prime numbers less than 1000

    list<int> numbers;
    list<int> prime;


    cout<<"Prime numbers less than 1000"<<endl;
    for ( list<int>::iterator it=prime.begin() ; it!=prime.end() ; ++it )
        cout<<"  "<<(*it);
    cout<<endl<<endl;
    }