Submission #821797

#	Time	Username	Problem	Language	Result	Execution time	Memory
821797		tch1cherin	Plus Minus (BOI17_plusminus)	C++17	100 / 100	98 ms	11728 KiB

plusminus

// govnokoded by tch1cherin
#include <bits/stdc++.h>
using namespace std;

const int MOD = 1e9 + 7;

int get_power(int p) {
  if (p < 30) {
    return 1 << p;
  }
  int ans = 1, val = 2;
  for (int i = 0; i <= __lg(p); i++, val = 1LL * val * val % MOD) {
    if ((p >> i) & 1) {
      ans = 1LL * ans * val % MOD;
    }
  }
  return ans;
}

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  int N, M, K;
  cin >> N >> M >> K;
  map<int, char> row, col;
  bool good[4] = {true, true, true, true};
  for (int i = 0; i < K; i++) {
    char c;
    int x, y;
    cin >> c >> x >> y;
    good[((x + y) & 1) ^ (c == '+') ^ 1] = false;
    if (row.count(x) && (row[x] ^ (6 * (y & 1))) != c) {
      good[2] = false;
    }
    if (col.count(y) && (col[y] ^ (6 * (x & 1))) != c) {
      good[3] = false;
    }
    row[x] = c ^ (6 * (y & 1)), col[y] = c ^ (6 * (x & 1));
  }
  int ans = 0;
  if (good[0]) {
    ans += MOD - 1;
  }
  if (good[1]) {
    ans += MOD - 1, ans %= MOD;
  }
  if (good[2]) {
    ans += get_power(N - row.size()), ans %= MOD;
  }
  if (good[3]) {
    ans += get_power(M - col.size()), ans %= MOD;
  }
  cout << ans << "\n";
}

• Subtask 1: 12 / 12
• Subtask 2: 42 / 42
• Subtask 3: 46 / 46