16(for)

#include <iostream>

using namespace std;

int main()
{
    int a,b;
    cout<<"A=";
    cin>>a;
    cout<<"B=";
    cin>>b;
    if(a<=b){
        for(int i =a;i<b+1;i++){
            if(i<0&&i%2==0){
                cout<<i<<" ";
            }
        }
    }
    else{
        cout<<"error";
    }
    return 0;
}