Submission #1040837

#	Time	Username	Problem	Language	Result	Execution time	Memory
1040837		12345678	Colors (BOI20_colors)	C++17	0 / 100	1 ms	436 KiB

Colors

#include <bits/stdc++.h>

using namespace std;

#define ll long long

ll n, tmp;

int query(ll x)
{
    cout<<"? "<<x<<endl;
    cin>>tmp;
    return tmp;
}

int main()
{
    cin>>n;
    ll dir=1, st=1, cur=1, l=1, r=n;
    while (l<r)
    {
        ll md=(l+r)/2;
        if (cur+dir*md>=1) cur+=dir*md;
        else st+=1-(cur+dir*md), cur=1;
        l=md+1;
        dir=-dir;
    }
    query(st);
    cur=st, dir=1, l=1, r=n;
    while (l<r)
    {
        ll md=(l+r)/2;
        cur+=dir*md;
        if (query(cur)) r=md;
        else l=md+1;
        dir=-dir;
    }
    cout<<"= "<<l<<endl;
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 13
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 33