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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#666309#8939. Permutationxh_team#WA 1ms3712kbC++201.8kb2024-10-22 17:45:102024-10-22 17:45:12

Judging History

This is the latest submission verdict.

  • [2024-10-22 17:45:12]
  • Judged
  • Verdict: WA
  • Time: 1ms
  • Memory: 3712kb
  • [2024-10-22 17:45:10]
  • Submitted

answer

#include <bits/stdc++.h>
using namespace std;
const int N = 2014;

mt19937 rnd(time(0));

int a[] = {-1, 4, 7, 2, 6, 5, 1, 9};

int ask(int l, int r) {
    cout << '?' << ' ' << l << ' ' << r << endl;
    int x;
    cin >> x;
    return x;


    // int fi = -1, se = -1;
    // for (int i = l; i <= r; i++) {
    //     fi = max(fi, a[i]);
    // }
    // int x = -1;
    // for (int i = l; i <= r; i++) {
    //     if (a[i] != fi && a[i] > se) {
    //         se = a[i];
    //         x = i;
    //     }
    // }
    // return x;
}

int n, p, ans;
void dfs(int l, int r) {
    if (r - l == 1) {
        ans = l + r - p;
        return;
    }
    if (r - l == 2) {
        if (p == l) {
            int q = ask(l + 1, r);
            ans = l + 1 + r - q;
        } else if (p == r) {
            int q = ask(l, l + 1);
            ans = l + l + 1 - q;
        } else {
            int q = ask(l, l + 1);
            if (p == q) {
                ans = l;
            } else {
                ans = r;
            }
        }
        return;
    }
    int mid = l - 1 + (rnd() & 1 ? (r - l + 1) / 3 : (r - l + 1) / 3 * 2);
    if (l == mid) mid++;
    if (mid + 1 == r) mid--;
    if (p <= mid) {
        int q = ask(l, mid);
        if (p == q) {
            dfs(l, mid);
        } else {
            p = ask(mid + 1, r);
            dfs(mid + 1, r);
        }
    } else {
        int q = ask(mid + 1, r);
        if (p == q) {
            dfs(mid + 1, r);
        } else {
            p = ask(l, mid);
            dfs(l, mid);
        }
    }

}

void solve() {
    cin >> n;
    p = ask(1, n);
    dfs(1, n);
    cout << '!' << ' ' << ans << endl;
}

int main() {
    ios_base::sync_with_stdio(false);

    int tt;
    cin >> tt;
    while (tt--) solve();

    return 0;
}

详细

Test #1:

score: 100
Accepted
time: 1ms
memory: 3712kb

input:

3
5
3
3
5
6
6
3
1
4
3
3

output:

? 1 5
? 3 5
? 4 5
! 4
? 1 6
? 3 6
? 1 2
! 2
? 1 4
? 3 4
! 4

result:

ok Correct (3 test cases)

Test #2:

score: -100
Wrong Answer
time: 0ms
memory: 3708kb

input:

10000
10
2
2
1
3
3
10
10
10
10
8
7
10
5
5
4
10
9

output:

? 1 10
? 1 6
? 1 2
? 3 6
? 3 4
! 4
? 1 10
? 4 10
? 6 10
? 8 10
? 6 7
! 6
? 1 10
? 4 10
? 4 5
? 6 10
? 8 10
? 6 7

result:

wrong answer Too many queries , n = 10 , now_q 6 (test case 3)