Submission #1173560

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Source Code Expand

#include <algorithm>
#include <array>
#include <cassert>
#include <cstdio>
#include <cstring>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <sstream>
#include <unordered_map>
#include <vector>


#define INF 1000000002486618624LL
#define MOD 1000000007
#define ALL(x) std::begin(x), std::end(x)


#define X(x) ((x) % W2)
#define Y(x) ((x) / W2)
#define XY(x, y) ((y) * W2 + (x))


int H, W, K, T, W2, W2W2;

std::array<int, 450> P, Q;

template<typename T>
using board_t = std::array<T, 1024>;


board_t<char> board;


void debugout(int t)
{
  for (int i = 0, p = 0; i < W2; i ++) {
    std::cerr << "t=" << t << ' ';
    for (int j = 0; j < W2; j ++, p ++)
      std::cerr << board[p];
    std::cerr << std::endl;
  }
}


int main(int argc, char** argv)
{
  std::cin.tie(0);
  std::ios_base::sync_with_stdio(0);

  std::cin >> H >> W >> K >> T;

  W2 = W + 2;

  W2W2 = W2 * W2;

  std::fill(ALL(board), '.');

  for (int i = 0; i < W2; i ++)
    board[XY(i, 0)] = board[XY(i, W + 1)] = board[XY(0, i)] = board[XY(W + 1, i)] = '#';

  for (int i = 0; i < K; i ++) {
    int a, b, c, d;

    std::cin >> a >> b >> c >> d;

    P[i] = XY(b, a);
    Q[i] = XY(d, c);

    board[P[i]] = 'X';
  }

  debugout(-1);

  std::vector<std::string> a;

  for (int t = 0; t < T; t ++) {
    std::string s = std::string(K, '-');

    for (int i = 0; i < K; i ++) {
      int p = P[i], px = X(p), py = Y(p), pp;
      int q = Q[i], qx = X(q), qy = Y(q);

      int dx = qx - px, dy = qy - py;

      // std::cerr << "  t=" << t << " i=" << i << " p=" << px << ' ' << py << " q=" << qx << ' ' << qy << std::endl;

      if (dx < 0 && board[p] == 'X' && board[pp = p - 1] == '.') {
        board[p] = '!';
        
        board[P[i] = pp] = 'X';
        
        s[i] = 'L';
      }
      else if (dx > 0 && board[p] == 'X' && board[pp = p + 1] == '.') {
        board[p] = '!';
        
        board[P[i] = pp] = 'X';
        
        s[i] = 'R';
      }
      
      if (dy < 0 && board[p] == 'X' && board[pp = p - W2] == '.') {
        board[p] = '!';
        
        board[P[i] = pp] = 'X';
        
        s[i] = 'U';
      }
      else if (dy > 0 && board[p] == 'X' && board[pp = p + W2] == '.') {
        if (board[pp = p + W2] == '.') {
          board[p] = '!';
          
          board[P[i] = pp] = 'X';
          
          s[i] = 'D';
        }
      }
    }

    a.push_back(s);

#if 0
    debugout(t);
#endif

    for (int i = 0; i < W2W2; i ++)
      if (board[i] == '!')
        board[i] = '.';
  }

  std::cout << a.size() << std::endl;

  for (const auto& s : a)
    std::cout << s << std::endl;

  return 0;
}

Submission Info

Judge Result