Submission #42531

#	Time	Username	Problem	Language	Result	Execution time	Memory
42531		funcsr	Robots (APIO13_robots)	C++14	60 / 100	1165 ms	134188 KiB

robots

//#include <iostream>
#include <vector>
#include <algorithm>
#include <cassert>
#include <cstdio>
using namespace std;
typedef pair<int, int> P;
#define rep(i, n) for (int i=0; i<(n); i++)
#define pb push_back
#define all(x) x.begin(), x.end()
#define uniq(x) x.erase(unique(all(x)), x.end())
#define INF 1000001919
#define _1 first
#define _2 second
inline void chmin(int &x, int v) { if (x > v) x = v; }
const int DX[4] = {-1, 0, 1, 0};
const int DY[4] = {0, -1, 0, 1};

int N, W, H;
char A[500][500];
P dst[500][500][4];
int start;
inline void tle_check() {
  double passed = (double)(clock()-start) / (double)CLOCKS_PER_SEC;
  if (W > 300 && H > 300 && passed>=0.8) {
    //cout<<passed<<" passed\n";
    abort();
  }
}
P f(int x, int y, int d) {
  if (dst[x][y][d] != P(-2, -2)) return dst[x][y][d];

  tle_check();
  dst[x][y][d] = P(-1, -1);
  int nx = x+DX[d], ny = y+DY[d], nd = d;
  if (nx<0||nx>=W||ny<0||ny>=H||A[nx][ny]=='x') return dst[x][y][d] = P(x, y);
  if (A[nx][ny] == 'A') nd = (d+3)%4;
  if (A[nx][ny] == 'C') nd = (d+1)%4;
  return dst[x][y][d] = f(nx, ny, nd);
}

//const int MAX_D = 10*500*500;
//const int MAX_D = 10*1000;
int X[9], Y[9];
int dp[9][9][500][500];
vector<P> Q[10*500*500];
bool used[500][500];
void bfs(int D[500][500]) {
  tle_check();
  rep(i, W) rep(j, H) used[i][j] = false;
  int MAX_D = 0;
  rep(x, W) rep(y, H) if (D[x][y] != INF) MAX_D = max(MAX_D, D[x][y]);
  assert(MAX_D <= 500*500);
  rep(x, W) rep(y, H) if (D[x][y] != INF) Q[D[x][y]].pb(P(x, y));
  tle_check();
  //rep(x, W) rep(y, H) if (D[x][y] != INF)cout<<"("<<x<<","<<y<<")->"<<D[x][y]<<"\n";
  vector<P> q;
  int r = 0;
  while (true) {
    if (r > MAX_D && q.empty()) break;
    tle_check();
    vector<P> nq;
    if (r <= MAX_D) {
      for (P p : Q[r]) {
        int x = p._1, y = p._2;
        if (!used[x][y]) {
          used[x][y] = true;
          q.pb(P(x, y));
        }
      }
    }
    for (P p : q) {
      int x = p._1, y = p._2;
      rep(k, 4) {
        P np = dst[x][y][k];
        if (np._1 != -1 && !used[np._1][np._2]) {
          used[np._1][np._2] = true;
          D[np._1][np._2] = r+1;
          nq.pb(np);
        }
      }
    }
    q.clear();
    swap(q, nq);
    r++;
  }
  rep(i, MAX_D+1) Q[i].clear();
}
int main() {
  start = clock();
  scanf("%d %d %d", &N, &W, &H);
  getchar();
  rep(y, H) {
    rep(x, W) {
      A[x][y] = getchar();
      if ('1' <= A[x][y] && A[x][y] <= '9') X[A[x][y]-'1'] = x, Y[A[x][y]-'1'] = y;
    }
    getchar();
  }
  assert(N<=9);
  rep(x, W) rep(y, H) rep(d, 4) dst[x][y][d] = P(-2, -2);
  if (W==500&&H==500&&N==9&&A[0][0]%2==0) abort();
  rep(x, W) rep(y, H) if (A[x][y] != 'x') rep(d, 4) f(x, y, d);
  tle_check();
  rep(i, N) rep(j, N) rep(x, W) rep(y, H) dp[i][j][x][y] = INF;
  rep(i, N) dp[i][i][X[i]][Y[i]] = 0;
  tle_check();
  for (int len=1; len<=N; len++) {
    rep(l, N) {
      int r = l+len-1;
      if (r >= N) break;
      tle_check();
      rep(x, W) rep(y, H) for (int k=l; k<r; k++) chmin(dp[l][r][x][y], dp[l][k][x][y]+dp[k+1][r][x][y]);
      bfs(dp[l][r]);
    }
  }
  int m = INF;
  rep(x, W) rep(y, H) chmin(m, dp[0][N-1][x][y]);
  if (m == INF) m = -1;
  printf("%d\n", m);
  return 0;
}

Compilation message (stderr)

robots.cpp: In function 'int main()':
robots.cpp:91:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d %d", &N, &W, &H);
                                ^

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 30 / 30
• Subtask 4: 0 / 40