#include <stdio.h>
 
int calculate(int *arr, int size) {
    if (size <= 0) return 0;
    if (size == 1) return *arr;
 
    int mid = size / 2;
    int left = calculate(arr, mid);
    int right = calculate(arr + mid, size - mid);
 
    int *ptr = arr;
    for (int i = 0; i < size; i++) {
        *ptr = (*ptr + i) % 3 == 0 ? left : right;
        ptr++;
    }
 
    return *(arr + size - 1);
}
 
int main() {
    int values[4] = {2, 4, 6, 8};
    int result = calculate(values, 4);
    printf("%d %d %d %d %d\n", values[0], values[1], values[2], values[3], result);
    return 0;
}

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