#include <iostream>
using namespace std;
 
struct node {
    int info;
    node *next;
};
 
int Sum_Even_Values(node *head)
{
    int sum = 0;
    if (head) {
        if ((head->info % 2) == 0) {
            cout << " + " << head->info;
            sum = head->info;
        }
        sum += Sum_Even_Values(head->next);
    }
    return sum;
}
 
int main() {
    // ignore that the nodes are on the stack instead of the heap,
    // this is just for demonstration purposes, how the nodes are
    // allocated is irrelevant...
    node nodes[10];
    for(int i = 0; i < 10; ++i) {
        nodes[i].info = i+1;
        nodes[i].next = &nodes[i+1];
    }
    nodes[9].next = 0;
 
    int sum = Sum_Even_Values(nodes);
    cout << " = " << sum;
 
    return 0;
}

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