Submission #867334

#	Time	Username	Problem	Language	Result	Execution time	Memory
867334		sleepntsheep	Aliens (IOI07_aliens)	C++17	10 / 100	1 ms	596 KiB

aliens

#include <iostream>
#include <cassert>
#include <vector>
#include <algorithm>
#include <deque>
#include <set>
#include <utility>
#include <array>

using namespace std;
#define ALL(x) x.begin(), x.end()
#define ShinLena cin.tie(nullptr)->sync_with_stdio(false);
using ll = long long;

int m, n, x, y, bl, bt, br;

bool examine(int x, int y)
{
    cout << "examine " << x << ' ' << y << '\n' << flush;
    char s[6]{0};
    cin >> s;
    return s[0] == 't';
}

void solution(int x, int y)
{
    cout << "solution " << x << ' ' << y << "\n" << flush;
    exit(0);
}

void find_border()
{
    int l = 1, r = x-1;
    while (l <= r)
    {
        int o = (l+r)/2;
        if (examine(o, y))
        {
            int oo = (o+x)/2;
            if (examine(oo, y)) r = o - 1;
            else l = oo + 1, bl = oo;
        }
        else l = o + 1, bl = o;
    }

    l = x+1, r = n;
    while (l <= r)
    {
        int o = (l+r)/2;
        if (examine(o, y))
        {
            int oo = (x+o)/2;
            if (examine(oo, y)) l = o + 1;
            else r = oo - 1, br = oo;
        }
        else r = o - 1, br = o;
    }

    m = br - bl - 1;
    assert(m%2);

    l = 1, r = y - 1;
    while (l <= r)
    {
        int o = (l+r)/2;
        if (examine(x, o))
        {
            int oo = (o+y)/2;
            if (examine(x, oo)) r = o - 1;
            else l = oo + 1, bt = oo;
        }
        else l = o + 1, bt = o;
    }
    x = bl + 1; y = bt + 1;
    assert(examine(x, y));
}

void find_11()
{
    for (; x>2*m && examine(x-2*m, y); x-=2*m);
    for (; y>2*m && examine(x, y-2*m); y-=2*m);
}

void find_middle()
{
    x += 2*m, y += 2*m;
    x += m/2, y += m/2;
}

int main()
{
    ShinLena;
    cin >> n >> x >> y;
    find_border();
    find_11();
    find_middle();
    solution(x, y);
    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 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