Submission #1123070

#	Time	Username	Problem	Language	Result	Execution time	Memory
1123070		thangdz2k7	Zagrade (COI20_zagrade)	C++20	100 / 100	340 ms	1132 KiB

zagrade

// author : thembululquaUwU
// 3.9.2024

#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second

using namespace std;
using ll = long long;
using ii = pair <int, int>;
using vi = vector <int>;

const int MaxN = 2e5;
const int mod = 1e9 + 7;

void maxl(auto &a, auto b) {a = max(a, b);}
void minl(auto &a, auto b) {a = min(a, b);}

bool ask(int a, int b){
    cout << "? " << a + 1 << ' ' << b + 1 << endl;
    int t; cin >> t;
    return t;
}

void solve(){
    int n, q; cin >> n >> q;
    string ans;
    ans.resize(n);
    vector <int> stk;
    for (int i = 0; i < n; ++ i){
        if (stk.empty() || !ask(stk.back(), i)){
            ans[i] = '(';
            stk.pb(i);
        }
        else {
            ans[i] = ')';
            stk.pop_back();
        }
    }
    int sz = stk.size();
    for (int i = 0; i < sz; ++ i)
        ans[stk[i]] = i * 2 < sz ? ')' : '(';

    cout << "! " << ans << endl;
}

int main(){
    if (fopen("pqh.inp", "r")){
        freopen("pqh.inp", "r", stdin);
        freopen("pqh.out", "w", stdout);
    }

    int t = 1; // cin >> t;
    while (t --) solve();
    return 0;
}

Compilation message (stderr)

zagrade.cpp: In function 'int main()':
zagrade.cpp:50:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   50 |         freopen("pqh.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
zagrade.cpp:51:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   51 |         freopen("pqh.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 7 / 7
• Subtask 3: 57 / 57
• Subtask 4: 22 / 22