Submission #867318

#	Time	Username	Problem	Language	Result	Execution time	Memory
867318		Ning07	Aliens (IOI07_aliens)	C++17	0 / 100	2 ms	596 KiB

aliens

#pragma warning(disable : 4996)
#include<bits/stdc++.h>
using namespace std;

using ll = long long;
#define L(i,j,k) for(int i=(j);i<=(k);i++)
#define R(i,j,k) for(int i=(j);i>=(k);i--)

int n, x_given, y_given, sz;
void read() {
    cin >> n >> x_given >> y_given;
    return;
}
bool ask(int x, int y) {
    cout << "examine " << x << ' ' << y << endl;
    string s; cin >> s;
    return s == "true";
}
bool is_grass(int x, int y) {
    if (x <= 0 || x >= n + 1 || y <= 0 || y >= n + 1) return false;
    return ask(x, y);
}
pair<int, int> last_black(int x, int y, int dx, int dy) {
    int t = 0;
    while (is_grass(x + dx * (1 << (t + 1)), y + dy * (1 << (t + 1)))) t++;
    if (t == 0) return make_pair(x, y);
    return last_black(x + dx * (1 << t), y + dy * (1 << t), dx, dy);
}
int count_block(int x, int y, int dx, int dy) {
    int t = 0;
    while (is_grass(x + dx * sz * t, y + dy * sz * t)) t++;
    return t;
}
void is_centre(int x, int y) {
    if (x <= 0 || x >= n + 1 || y <= 0 || y >= n + 1) return;
    bool ok = true;
    ok &= count_block(x, y, 1, 0) == 1;
    ok &= count_block(x, y, -1, 0) == 1;
    ok &= count_block(x, y, 0, 1) == 1;
    ok &= count_block(x, y, 0, -1) == 1;
    if (ok) {
        cout << "solution: " << x << ' ' << y << endl;
        exit(0);
    }
}
void find_centre() {
    pair<int, int> a = last_black(x_given, y_given, 0, 1);
    pair<int, int> b = last_black(x_given, y_given, 0, -1);
    pair<int, int> c = last_black(x_given, y_given, 1, 0);
    pair<int, int> d = last_black(x_given, y_given, -1, 0);
    int difx = max({ a.first,b.first,c.first,d.first }) - min({ a.first,b.first,c.first,d.first });
    int dify = max({ a.second,b.second,c.second,d.second }) - min({ a.second,b.second,c.second,d.second });
    sz = difx + 1; sz *= 2;
    int midx = min({ a.first,b.first,c.first,d.first }) + difx / 2;
    int midy = min({ a.second,b.second,c.second,d.second }) + dify / 2;
    for (int i = -4; i <= 4; i++) {
        for (int j = -4; j <= 4; j++) {
            is_centre(midx + i * sz, midy + j * sz);
        }
    }
}
int main() {
    read();
    find_centre();
}

Compilation message (stderr)

aliens.cpp:1: warning: ignoring '#pragma warning ' [-Wunknown-pragmas]
    1 | #pragma warning(disable : 4996)
      |

• Subtask 1: 0 / 10
• Subtask 2: 0 / 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