Submission #1197800

#	Time	Username	Problem	Language	Result	Execution time	Memory
1197800		nvc2k8	Colors (BOI20_colors)	C++20	0 / 100	0 ms	436 KiB

Colors

#include <bits/stdc++.h>
#define TASK "colors"
#define INT_LIM (int) 2147483647
#define LL_LIM (long long) 9223372036854775807
#define endl '\n'
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define BIT(i,x) (((i)>>(x))&1)
#define FOR(i,a,b) for(int i = (a); i<=(b); i++)
#define FORD(i,a,b) for(int i = (a); i>=(b); i--)
#define ll long long
#define pii pair<int,int>
using namespace std;
///------------------------------------------///
ll n;
#define ask(x) cout << "? " << (x) << endl; cout.flush();
#define answer(x) cout << "= " << (x) << endl; cout.flush();

void inp()
{
    cin >> n;
}

ll ret = 0, lb = 0, rb = LL_LIM;
int querycnt = 0;
set<ll> dd;

void solve()
{
    int response;
    ll la = n-(1LL<<__lg(n));
    ask(la); querycnt++; dd.insert(la);
    cin >> response;

    ll dir = 1;

    FORD(pos, 59, 0)
    {
        ll delta = ret+(1LL<<pos);
        if (delta>=n || delta<1) continue;
        if (la+dir*delta>n || la+dir*delta<1) dir = -dir;
        ll nw = la+dir*delta;
//        cout << delta-2068728389572138 << endl; cout.flush();

        if (dd.count(nw)) assert(false);
        ask(nw); querycnt++; dd.insert(nw);
        la = nw;
        cin >> response;
        if (response==0)
        {
            ret+= (1LL<<pos);
            lb = max(lb, delta);
        }
        else
        {
            rb = min(rb, delta);
        }
    }

    if (querycnt>64) assert(false);

    answer(ret+1);
}

signed main()
{
    ///--------------------------///
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    if (fopen(TASK".INP","r")!=NULL)
    {
        freopen(TASK".INP","r",stdin);
        freopen(TASK".OUT","w",stdout);
    }
    ///--------------------------///

    int NTEST = 1;
    //cin >> NTEST;

    while (NTEST--)
    {
        inp();
        solve();
    }

    return 0;
}

///------------------------------------------///

Compilation message (stderr)

Colors.cpp: In function 'int main()':
Colors.cpp:73:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   73 |         freopen(TASK".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
Colors.cpp:74:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   74 |         freopen(TASK".OUT","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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