Submission #1122437

#	Time	Username	Problem	Language	Result	Execution time	Memory
1122437		12345678	Zagrade (COI20_zagrade)	C++17	100 / 100	346 ms	1588 KiB

zagrade

#include <bits/stdc++.h>

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

using namespace std;

const int nx=1e5+5;

int n, q, cnt, res[nx], x, jmp[nx], f[nx], qcnt=0;

int query(int l, int r)
{
    cout<<"? "<<l<<' '<<r<<'\n';
    fflush(stdout);
    cin>>x;
    return x;
}

void solve(int l, int r)
{
    if (l<1||r>n||res[r]||f[r]) return;
    if (res[l]) 
    {
        solve(jmp[l], r);
        if (jmp[jmp[l]]) jmp[l]=jmp[jmp[l]];
        return;
    }
    if (query(l, r)) res[l]=1, res[r]=2, jmp[r]=l-1, cnt+=2, solve(l-1, r+1);
    else f[r]=1;
}

int main()
{
    cin>>n>>q;
    for (int i=1; i<=n; i++)
    {
        solve(i, i+1);
    }
    cnt=(n-cnt)/2;
    for (int i=1; i<=n; i++)
    {
        if (!res[i]&&cnt>0) cnt--, res[i]=2;
        else if (!res[i]) res[i]=1;
    }
    //cout<<'\n';
    cout<<"! ";
    for (int i=1; i<=n; i++) cout<<((res[i]==1)?'(':')');
    fflush(stdout);
}

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