#include <iostream>
#include <vector>
using namespace std;


vector<int> t[10];


// some auxillary function, that returns sometimes 0, sometimes non-zero
int auxillary (const vector<int> & v, int arg) {
    int result = 0;

    // <smth>
    // here may be anything, complex enough to stop optimizer
    for (size_t i=0; i<v.size(); ++i)
        if (arg <= v[i])
            ++result;
    // </smth>

    cout << "auxillary = " << result << endl;
    return result;
}


// some complex recursive function, that performs calls to auxillary()
int query (int v, int tl, int tr, int lx, int rx, int arg) {
    if (lx > rx)  return 0;

    // sometimes the recursion results in calling auxillary()
    if (tl == lx && rx == tr) {
        cout << "call auxillary (t[" << v << "], " << arg << "):" << endl;
        return auxillary (t[v], arg);
    }

    // <smth>
    // here might be any complex recursive calls, resulting in auxillary() calls
    int tm = (tl + tr) / 2;
    int ans1 = query (v*2, tl, tm, lx, min(rx,tm), arg);
    int ans2 = query (v*2+1, tm+1, tr, max(lx,tm+1), rx, arg);
    int ans = ans1 + ans2;
    // </smth>

    //cout << "query = " << ans << endl;
    // ^^^^^ UNCOMMENT THIS LINE TO MAKE THE PROGRAM WORK OK

    return ans;
}


int main() {
    t[9].push_back (456); // some data to make auxillary() return non-zero sometimes

    cout << "global ans = " << query (1, 0, 5, 1, 2, 123) << endl;
    // ^^^^^ SHOULD OUTPUT "1"
}