#include "prize.h"
#include <vector>
#include <algorithm>
#include <set>
using namespace std;
int m, res;
bool flag = false;
vector<int> mem[200005];
vector<int> qr(int x){
if(mem[x].size() == 0) mem[x] = ask(x);
return mem[x];
}
void solve(int l, int r, int num, int bef){
if(num == 0) return;
if(l > r) return;
int mid = (l+r)/2;
vector<int> resp = qr(mid);
if(resp[0]+resp[1] == 0){
res = mid;
flag = true;
return;
}
int b = mid;
while(resp[0]+resp[1] != m && b < r){
b++;
resp = qr(b);
if(resp[0]+resp[1] == 0){
res = b;
flag = true;
return;
}
}
if(resp[0]+resp[1] == m){
solve(l, mid-1, resp[0]-(b-mid)-bef, bef);
if(flag) return;
solve(b+1, r, num-(resp[0]-bef), resp[0]);
if(flag) return;
} else{
solve(l, mid-1, num, bef);
}
return;
}
int find_best(int n) {
if(n <= 5000){
for(int i=0; i<n; i++){
vector<int> resp = qr(i);
if(resp[0]+resp[1] == 0) return i;
}
}
vector<int> resp;
set<int> s;
for(int x=0; x<480; x++){
int i = x;
resp = qr(i);
if(resp[0]+resp[1] == 0) return i;
s.insert(resp[0]+resp[1]);
m = max(m, resp[0]+resp[1]);
if(s.size() == 4) break;
}
solve(0, n-1, m, 0);
return res;
}
