#include "prize.h"
#include <vector>
#include <algorithm>
using namespace std;
int m, res;
void solve(int l, int r, int num){
if(num == 0) return;
if(l > r) return;
int mid = (l+r)/2;
vector<int> resp = ask(mid);
if(resp[0]+resp[1] == 0){
res = mid;
return;
}
int b = mid;
while(resp[0]+resp[1] != m && b < r){
b++;
resp = ask(b);
}
if(resp[0]+resp[1] == m){
solve(l, mid-1, resp[0]-(b-mid));
solve(b+1, r, resp[1]);
} else{
solve(l, mid-1, num);
}
return;
}
int find_best(int n) {
if(n <= 3000){
for(int i=0; i<n; i++){
vector<int> resp = ask(i);
if(resp[0]+resp[1] == 0) return i;
}
}
vector<int> resp;
for(int i=0; i<500; i++){
resp = ask(i);
if(resp[0]+resp[1] == 0) return i;
m = max(m, resp[0]+resp[1]);
}
solve(0, n-1, m);
return res;
}
