Submission #669740

#	Time	Username	Problem	Language	Result	Execution time	Memory
669740		mychecksedad	Colors (BOI20_colors)	C++17	0 / 100	1 ms	208 KiB

Colors

/* Author : Mychecksdead */
#include<bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
typedef long long int ll;
typedef long double ld;
#define MOD1 (1000000000+7)
#define MOD (998244353)
#define PI 3.1415926535
#define pb push_back
#define setp() cout << setprecision(15)
#define all(x) x.begin(), x.end()
#define debug(x) cerr << #x << " is " << x << '\n';
const int N = 1e6+100, M = 1e5+10, F = 2147483646, K = 20;


bool ask(int c){
	cout << "? " << c << endl;
	bool r; cin >> r;
	return r;
}
void result(int k){
	cout << "= " << k << endl;
	exit(0);
}

int n;
void solve(){
	cin >> n;
	vector<int> v;
	int l = 1, r = n;


	
	while(l <= r){
		v.pb(l);
		if(l != r)
			v.pb(r);
		if(l + 2 < r - 2)
			l+=2, r-=2;
		else
			l++, r--;
	}
	vector<bool> used(n+1);
	ask(v[0]);
	used[v[0]] = 1;
	for(int i = 1; i < v.size(); ++i){
		bool b = ask(v[i]);
		used[v[i]] = 1;
		if(b == 0){
			int d = abs(v[i] - v[i - 1]) + 1;


			if(i > 1 && abs(v[i - 1] - v[i - 2]) == d) result(d);
			
			if(d == n){
				result(d);
			}

			if(v[i] - d >= 1 && !used[v[i] - d]){
				b = ask(v[i] - d);
			}else if(v[i] + d <= n && !used[v[i] + d]){
				b = ask(v[i] + d);
			}else{
				for(int i = 1; i + d <= n; ++i){
					if(!used[i] && !used[i + d]){
						ask(i);
						b = ask(i+d);
						break;
					}
				}
			}

			if(b == 1){
				result(d);
			}else{
				result(d + 1);
			}
		}
	}
	result(1);
}




int main(){
    cin.tie(0); ios::sync_with_stdio(0);
    int T = 1, aa;
    // cin >> T;aa=T;
    while(T--){
        // cout << "Case #" << aa-T << ": ";
        solve();
    }
    return 0;
 
}

Compilation message (stderr)

Colors.cpp: In function 'void solve()':
Colors.cpp:48:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |  for(int i = 1; i < v.size(); ++i){
      |                 ~~^~~~~~~~~~
Colors.cpp: In function 'int main()':
Colors.cpp:90:16: warning: unused variable 'aa' [-Wunused-variable]
   90 |     int T = 1, aa;
      |                ^~

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