#include <iostream>

using namespace std;

int suma(int x, int y, int &z)
{
    z=0;
    for(int i=x; i<=y; i++)
    {
        if(i%2==0)
            z=z+i;
    }
}
int main()
{
 int x=12, y=23, z;
 suma(x,y,z);
 cout<<z;
}