Submission #1127424

#	Time	Username	Problem	Language	Result	Execution time	Memory
1127424		Tymond	Colors (BOI20_colors)	C++20	0 / 100	1 ms	424 KiB

Colors

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::high_resolution_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }

    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

struct pair_hash{
  size_t operator()(const pair<int,int>&x)const{
    return hash<long long>()(((long long)x.first)^(((long long)x.second)<<32));
  }
};

int ask(ll k){
    cout << "? " << k << endl;
    int res;
    cin >> res;
    return res;
}

int main(){
    /*ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    cout.tie(NULL);*/
    
    ll n;
    cin >> n;

    vll vec;
    ll k = n / 2;
    while(k > 0){
        vec.pb(k);
        k = k / 2;
    }
    reverse(all(vec));
    ll p = 1LL;
    for(auto ele : vec){
        if(ele + p <= n){
            p += ele;
        }else{
            p -= ele;
        }
    }

    unordered_set<ll> used;
    ask(p);
    used.insert(p);

    ll lo = 1LL;
    ll hi = n;
    ll mid;
    while(lo < hi){
        mid = (lo + hi) / 2;
        if(p + mid <= n && used.count(p + mid) == 0){
            p = (ll)p + mid;
        }else{
            p = (ll)p - mid;
        }

        if(ask(p)){
            hi = mid;
        }else{
            lo = mid + 1;
        }
        used.insert(p);
    }

    cout << "= " << lo << endl;

    return 0;
}

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