#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define MAX 101010
#define ln '\n'
#define bb ' '
#define abs(x) ((x)>0?(x):-(x))
ll query(ll x) {
cout << '?' << bb << x << endl;
ll ret;
cin >> ret;
return ret;
}
signed main() {
ll N;
cin >> N;
ll l, r, mid;
l = 0, r = N;
ll prev = N / 2;
query(prev);
ll res;
while (r - l > 1) {
mid = (l + r + 1) >> 1;
if (1 <= prev + mid && prev + mid <= N && 1 <= prev - mid && prev - mid <= N) {
ll a = min(abs(prev + mid - 1), abs(prev + mid - N));
ll b = min(abs(prev - mid - 1), abs(prev - mid - N));
if (a < b) {
prev += mid;
res = query(prev);
}
else {
prev -= mid;
res = query(prev);
}
}
else if (1 <= prev + mid && prev + mid <= N) {
prev += mid;
res = query(prev);
}
else if (1 <= prev - mid && prev - mid <= N) {
prev -= mid;
res = query(prev);
}
else {
query(1);
res = query(mid + 1);
}
if (res) r = mid;
else l = mid;
}
cout << '=' << bb << r << endl;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
364 KB |
OK (4 queries) |
2 |
Incorrect |
1 ms |
364 KB |
Hair color 1 was used multiple times |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
364 KB |
OK (4 queries) |
2 |
Incorrect |
1 ms |
364 KB |
Hair color 1 was used multiple times |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
364 KB |
OK (4 queries) |
2 |
Incorrect |
1 ms |
364 KB |
Hair color 1 was used multiple times |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
364 KB |
OK (4 queries) |
2 |
Incorrect |
1 ms |
364 KB |
Hair color 1 was used multiple times |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
364 KB |
OK (4 queries) |
2 |
Incorrect |
1 ms |
364 KB |
Hair color 1 was used multiple times |
3 |
Halted |
0 ms |
0 KB |
- |