oj.uz

Submission #804461

# Submission time Handle Problem Language Result Execution time Memory
804461 2023-08-03T08:51:47 Z rnl42 Colors (BOI20_colors) C++14
0 / 100
 300 ms 208 KB 
#include <bits/stdc++.h>
using namespace std;
#define int long long

int N;
unordered_set<int> used;

bool isvalid(int cur) {
    int mini = 1, maxi = N-1;
    bool parity = false;
    while (mini <= maxi) {
        int mid = (mini+maxi)>>1;
        int next;
        if (!parity) {
            next = cur+mid;
        } else {
            next = cur-mid;
        }
        if (next < 0 || next >= N) return false;
        mini = mid+1;
        cur = next;
        parity ^= 1;
    }
    return true;
}

inline bool query(int x) {
    used.insert(x);
    cout << "? " << x+1 << '\n' << flush;
    assert(x >= 0 && x < N);
    bool ret;
    cin >> ret;
    return ret;
}

signed main() {
    ios::sync_with_stdio(false), cin.tie(0), cout.tie(0);
    cin >> N;
    int mini = 1, maxi = N-1;
    int cur = max(N/3-10, 0ll);
    for (; !isvalid(cur); cur++);
    query(cur);
    bool parity = false;
    while (mini <= maxi) {
        int mid = (mini+maxi)>>1;
        int next;
        if (!parity) {
            next = cur+mid;
        } else {
            next = cur-mid;
        }
        if (query(next)) {
            maxi = mid;
        } else {
            mini = mid+1;
        }
        cur = next;
        parity ^= 1;
    }
    cout << "= " << mini << '\n';
}

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2386 ms 208 KB Time limit exceeded (wall clock)
2 Halted 0 ms 0 KB -

Subtask #2
0 / 13.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2386 ms 208 KB Time limit exceeded (wall clock)
2 Halted 0 ms 0 KB -

Subtask #3
0 / 21.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2386 ms 208 KB Time limit exceeded (wall clock)
2 Halted 0 ms 0 KB -

Subtask #4
0 / 24.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2386 ms 208 KB Time limit exceeded (wall clock)
2 Halted 0 ms 0 KB -

Subtask #5
0 / 33.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2386 ms 208 KB Time limit exceeded (wall clock)
2 Halted 0 ms 0 KB -