Submission #920468

#	Time	Username	Problem	Language	Result	Execution time	Memory
920468		zeta7532	Zagrade (COI20_zagrade)	C++17	71 / 100	568 ms	5432 KiB

zagrade

#include <bits/stdc++.h>
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
using ll = long long;
const ll mod = 998244353;
#define fi first
#define se second
#define rep(i,n) for(ll i=0;i<n;i++)
#define all(x) x.begin(),x.end()
#define faster ios::sync_with_stdio(false);cin.tie(nullptr)

int main() {
    ll N,Q;
    cin >> N >> Q;
    vector<char> ans(N,'-');
    ll l=0;
    ans[0]='(';
    ll r=1;
    set<ll> s;
    rep(i,N) s.insert(i);
    while(1){
        if(r>=N) break;
        cout << "?" << " " << l+1 << " " << r+1 << endl;
        ll q;
        cin >> q;
        if(q==0){
            ans[r]='(';
            l=r;
            r=l+1;
        }
        if(q==1){
            s.erase(l);
            s.erase(r);
            ans[r]=')';
            if(s.size()==0) break;
            if((*s.begin())>l){
                l=r+1;
                if(r+1!=N) ans[r+1]='(';
                r=l+1;
            }else{
                auto it=s.upper_bound(l);
                it--;
                l=*it;
                r=r+1;
            }
        }    
    }
    cout << "!" << " ";
    rep(i,N) cout << ans[i];
    cout << endl;
    return 0;
}

• Subtask 1: 14 / 14
• Subtask 2: 0 / 7
• Subtask 3: 57 / 57
• Subtask 4: 0 / 22