Submission #106682

#	Time	Username	Problem	Language	Result	Execution time	Memory
106682		SOIVIEONE	Aliens (IOI07_aliens)	C++14	20 / 100	6 ms	412 KiB

aliens

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

#define INF 1000000021
#define MOD 1000000007
#define pb push_back
#define sqr(a) (a)*(a)
#define M(a, b) make_pair(a,b)
#define F first
#define S second
#define all(x) (x.begin(), x.end())
#define deb(x) cerr << #x << " = " << x << '\n'
#define N 222222

using namespace std;
using namespace __gnu_pbds;

typedef long double ld;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> indexed_set;

const ld pi = 2 * acos(0.0);
template<class T> bool umin(T& a, T b){if(a>b){a=b;return 1;}return 0;}
template<class T> bool umax(T& a, T b){if(a<b){a=b;return 1;}return 0;}
template<class T, class TT> bool pal(T a, TT n){int k=0;for(int i=0;i<=n/2;i++){if(a[i]!=a[n-i-1]){k=1;break;}}return k?0:1;}

//int month[] = {0,31,28,31,30,31,30,31,31,30,31,30,31};

map<pll, bool> mp;
ll n, sk = 0;
bool ask(ll x, ll y)
{
	if(x <= 0 || x > n || y <= 0 || y > n)
		return 0;
	if(mp.count(M(x, y)))
		return mp[M(x, y)];
	sk ++;
	if(sk > 299)
	{
		while(1 > 0)
			sk ++;
	}
	cout << "examine " << x << ' ' << y << '\n';
	cout.flush();
	string q;
	cin >> q;
	return mp[M(x, y)] = (q[0] == 't');
}

int main()
{
	ll x, y;
	cin >> n >> x >> y;
	ll p = 1;
	while(p + x <= n && ask(x + p, y))
		p *= 2ll;
	ll l = x + p/2, r = min(x + p, n), hr = 0;
	for(int i = 1; i <= 40; i ++)
	{
		ll m = (l + r) >> 1ll;
		if(ask(m, y))
		{
			l = m + 1;
			hr = m;
		}
		else
			r = m;
	}
	if(ask(hr+1,y))
		hr++;
	p = 1;
	while(x - p >= 1 && ask(x - p, y))
		p *= 2ll;
	l = max(x - p, 1ll); r = x - p/2;
	ll hl = r;
	for(int i = 1; i <= 40; i ++)
	{
		ll m = (l + r) >> 1l;;
		if(!ask(m, y))
		{
			l = m + 1;
			hl = m;
		}
		else
			r = m;
	}
	if(hl!=r)
		hl ++;
	if(ask(hl-1, y))
		hl --;
	ll mm = hr - hl + 1;
	p = 1;
	while(y + p <= n && ask(x, y + p))
		p *= 2ll;
	l = y + p/2; r = min(y + p, n); ll v = 0;
	for(int i = 1; i <= 40; i ++)
	{
		ll m = (l + r) >> 1ll;
		if(ask(x, m))
		{
			l = m + 1;
			v = m;
		}
		else
			r = m;
	}
	if(ask(x, v + 1))
		v ++;
	ll up = v;
	while(ask(x, up+mm+mm))
		up += mm+mm;
	ll left = hl;
	while(ask(left-mm-mm, y))
		left -= (mm + mm);
	ll right = left + 5*mm-1;
	ll down = up - 5*mm+1;
	cout << "solution " << (left+right)/2ll << ' ' << (up + down)/2ll << '\n';
	cout.flush();
	


	return 0;
	//ios::sync_with_stdio(false);
	//cin.tie(0);
}

• Subtask 1: 0 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10