Submission #1219811

#	Time	Username	Problem	Language	Result	Execution time	Memory
1219811		thelegendary08	Colors (BOI20_colors)	C++17	0 / 100	0 ms	436 KiB

Colors

#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define int long long
#define vi vector<int>
#define vvi vector<vector<int>>
#define pii pair<int, int>
#define vpii vector<pair<int, int>>
#define vc vector<char>
#define vb vector<bool>
#define mii map<int,int>
#define f0r(i,n) for(int i=0;i<n;i++)
#define FOR(i,k,n) for(int i=k;i<n;i++)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define in(a) int a; cin>>a
#define in2(a,b) int a,b; cin>>a>>b
#define in3(a,b,c) int a,b,c; cin>>a>>b>>c
#define in4(a,b,c,d) int a,b,c,d; cin>>a>>b>>c>>d
#define vin(v,n); vi v(n); f0r(i,n){cin>>v[i];}
#define out(a) cout<<a<<'\n'
#define out2(a,b) cout<<a<<' '<<b<<'\n'
#define out3(a,b,c) cout<<a<<' '<<b<<' '<<c<<'\n'
#define out4(a,b,c,d) cout<<a<<' '<<b<<' '<<c<<' '<<d<<'\n'
#define pout(a) cout<<a.first<<' '<<a.second<<'\n'
#define vout(v) for(auto u : v){cout<<u<<' ';} cout<<'\n'
#define dout(a) cout<<a<<' '<<#a<<'\n'
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<'\n'
#define yn(x); if(x){cout<<"YES"<<'\n';}else{cout<<"NO"<<'\n';}
const int leg = 1e9 + 7;
const int mod = 998244353;
using namespace std;
int quer(int x){
	cout<<"? "<<x<<endl;
	int y; cin>>y; return y;
}
void answer(int x){
	cout<<"= "<<x<<endl;
}
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	//ifstream cin(".in");
	//ofstream cout(".out");
	in(n);
	if(n <= 64){
		int s = n/2;
		int cnt = 1;
		int l = s; int r = s;
		quer(s);
		while(cnt < n){
			int y;
			if(cnt % 2 == 1){
				y = quer(l-1);
				l--;
			}
			else{
				y = quer(r+1);
				r++;
			}
			if(y)break;
			cnt++;
		}
		answer(cnt);
	}
	else if(n <= 1e9){
        int lo = 1;
        int hi = n;
        set<int>vis;
        int lg = floor(log2(n)) + 3;
        while(lo < hi){
            int mid = lo + (hi - lo) / 2;
            int y;
            int cur = lg;
            bool done = 0;
            int cnt = 0;
            while(cur <= n - lg && cnt <= 100){
                if(cur <= n && cur + mid <= n && !vis.count(cur) && !vis.count(cur + mid)){
                    quer(cur); y = quer(cur + mid); done = 1; vis.insert(cur); vis.insert(cur + mid); break;
                }
                cur++;
                cnt++;
            }
            if(!done){
                for(int i = lg-1; i>=1; i--){
                    if(!vis.count(i) && !vis.count(i + mid) && i <= n && i + mid <= n){
                        quer(i); y = quer(i + mid); done = 1; vis.insert(i); vis.insert(i + mid); break;
                    }
                }
            }

            if(y == 1){
                hi = mid;
            }
            else lo = mid + 1;
        }
        cout<<"= "<<lo<<endl;
	}
	else{
        int lo = 1;
        int hi = n;
        int l1 = 1; int l2 = n;
        int l = 1;
        int cnt = 0;
        int pv = 0;
        while(l1 < l2){
            int mid = l1 + (l2 - l1) / 2;
            if(cnt % 2 == 1){
                l += (mid - pv);
            }
            pv = mid;
            l1 = mid + 1;
            //cout<<l1<<' '<<l2<<endl;
            cnt++;
        }

        cout<<"? "<<l<<endl;
        int y; cin>>y;
        int r = l;
        bool rig = 1;
        set<int>s;
        s.insert(l);
        while(lo < hi){
            int mid = lo + (hi - lo) / 2;
            if(l + mid <= n && !s.count(l+mid)){
                cout<<"? "<<l+mid<<endl;
                l += mid;
                s.insert(l);
            }
            else{
                cout<<"? "<<l-mid<<endl;
                l -= mid;
                s.insert(l);
            }
            /*
            if(rig){
                cout<<"? "<<l+mid<<endl;
                r = l + mid;
            }
            else{
                cout<<"? "<<r-mid<<endl;
                l = r-mid;
            }
            */

            int y; cin>>y;
            if(y == 1){
                hi = mid;
            }
            else lo = mid + 1;
            rig = !rig;
        }
        cout<<"= "<<lo<<endl;
	}

}

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