Problem p00213 (C++) — buggy submission, verdict: Runtime Error

#include <algorithm>
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>

using namespace std;

#define FOR(i, k, n) for (int i = (k); i < (int)(n); ++i)
#define REP(i, n) FOR(i, 0, n)
#define FORIT(i, c)                                                            \\
  for (__typeof((c).begin()) i = (c).begin(); i != (c).end(); ++i)

template <class T> void debug(T begin, T end) {
  for (T i = begin; i != end; ++i)
    cerr << *i << " ";
  cerr << endl;
}
inline bool valid(int x, int y, int W, int H) {
  return (x >= 0 && y >= 0 && x < W && y < H);
}

typedef long long ll;
const int INF = 100000000;
const double EPS = 1e-8;
const int MOD = 1000000007;
int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1};
int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1};
int W, H, N;
int b[16], k[16];
int s[10][10];
int ans[10][10];
int used[10][10];
int TX[20], TY[20];
class DFSError {};
void dfs(int idx) {
  if (idx == N) {
    if (ans[0][0] != -1)
      throw DFSError();
    REP(y, H) REP(x, W) ans[y][x] = used[y][x];
    return;
  }
  /*
  printf("idx = %d\\n", idx);
  REP(y, H){
    REP(x, W){
      cout << used[y][x];
      if(x != W - 1) cout << " ";
      else cout << endl;
    }
  }
  */
  int tx = TX[b[idx] - 1];
  int ty = TY[b[idx] - 1];
  // printf("idx = %d tx = %d ty = %d\\n", idx, tx, ty);

  assert(idx < N);
  assert(b[idx] >= 1 && b[idx] <= N);
  assert(tx != -1);
  for (int h = 1; h <= k[idx]; h++)
    if (k[idx] % h == 0) {
      int w = k[idx] / h;
      for (int by = 0; by > -h; by--)
        for (int bx = 0; bx > -w; bx--) {
          int sx = tx + bx;
          int sy = ty + by;
          bool ok = true;
          for (int y = 0; y < h; y++)
            for (int x = 0; x < w; x++) {
              if (!valid(sx + x, sy + y, W, H) || used[sy + y][sx + x] != -1)
                ok = false;
            }
          if (ok) {
            int tmp[10][10];
            memcpy(tmp, used, sizeof(used));
            for (int y = 0; y < h; y++)
              for (int x = 0; x < w; x++) {
                used[sy + y][sx + x] = b[idx];
              }
            dfs(idx + 1);
            memcpy(used, tmp, sizeof(used));
          }
        }
    }
}

int main() {
  while (cin >> W >> H >> N && (W | H | N)) {
    REP(i, N) cin >> b[i] >> k[i];
    REP(y, H) REP(x, W) cin >> s[y][x];
    try {
      memset(used, -1, sizeof(used));
      memset(ans, -1, sizeof(ans));
      memset(TX, -1, sizeof(TX));
      memset(TY, -1, sizeof(TY));
      REP(y, H)
      REP(x, W) if (s[y][x] > 0) TX[s[y][x] - 1] = x,
                                              TY[s[y][x] - 1] = y;
      REP(i, N) if (TX[i] == -1) {
        /*
        cerr << W << " " << H << " " << N << endl;
        REP(j, N) cerr << b[j] << " " << k[j] << endl;
        REP(y, H) { REP(x, W) cerr << s[y][x] << " "; cerr << endl; }
        assert("bord is dissapeared" == "");
        */
        throw 0;
      }
      dfs(0);
      if (ans[0][0] == -1)
        throw DFSError();
      REP(y, H) {
        REP(x, W) {
          cout << ans[y][x];
          if (x != W - 1)
            cout << " ";
          else
            cout << endl;
        }
      }
    } catch (...) {
      cout << "NA" << endl;
    }
  }
  return 0;
}

Error: 0

Fixed submission:

#include <algorithm>
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>

using namespace std;

#define FOR(i, k, n) for (int i = (k); i < (int)(n); ++i)
#define REP(i, n) FOR(i, 0, n)
#define FORIT(i, c)                                                            \\
  for (__typeof((c).begin()) i = (c).begin(); i != (c).end(); ++i)

template <class T> void debug(T begin, T end) {
  for (T i = begin; i != end; ++i)
    cerr << *i << " ";
  cerr << endl;
}
inline bool valid(int x, int y, int W, int H) {
  return (x >= 0 && y >= 0 && x < W && y < H);
}

typedef long long ll;
const int INF = 100000000;
const double EPS = 1e-8;
const int MOD = 1000000007;
int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1};
int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1};
int W, H, N;
int b[16], k[16];
int s[10][10];
int ans[10][10];
int used[10][10];
int TX[20], TY[20];
class DFSError {};
void dfs(int idx) {
  if (idx == N) {
    if (ans[0][0] != -1)
      throw DFSError();
    REP(y, H) REP(x, W) ans[y][x] = used[y][x];
    return;
  }
  /*
  printf("idx = %d\\n", idx);
  REP(y, H){
    REP(x, W){
      cout << used[y][x];
      if(x != W - 1) cout << " ";
      else cout << endl;
    }
  }
  */
  int tx = TX[b[idx] - 1];
  int ty = TY[b[idx] - 1];
  // printf("idx = %d tx = %d ty = %d\\n", idx, tx, ty);

  assert(idx < N);
  assert(b[idx] >= 1 && b[idx] <= N);
  assert(tx != -1);
  for (int h = 1; h <= k[idx]; h++)
    if (k[idx] % h == 0) {
      int w = k[idx] / h;
      for (int by = 0; by > -h; by--)
        for (int bx = 0; bx > -w; bx--) {
          int sx = tx + bx;
          int sy = ty + by;
          bool ok = true;
          for (int y = 0; y < h; y++)
            for (int x = 0; x < w; x++) {
              if (!valid(sx + x, sy + y, W, H) || used[sy + y][sx + x] != -1)
                ok = false;
            }
          if (ok) {
            int tmp[10][10];
            memcpy(tmp, used, sizeof(used));
            for (int y = 0; y < h; y++)
              for (int x = 0; x < w; x++) {
                used[sy + y][sx + x] = b[idx];
              }
            dfs(idx + 1);
            memcpy(used, tmp, sizeof(used));
          }
        }
    }
}

int main() {
  while (cin >> W >> H >> N && (W | H | N)) {
    REP(i, N) cin >> b[i] >> k[i];
    REP(y, H) REP(x, W) cin >> s[y][x];
    try {
      memset(used, -1, sizeof(used));
      memset(ans, -1, sizeof(ans));
      memset(TX, -1, sizeof(TX));
      memset(TY, -1, sizeof(TY));
      REP(y, H)
      REP(x, W) if (s[y][x] > 0) TX[s[y][x] - 1] = x,
                                              TY[s[y][x] - 1] = y;
      REP(i, N) if (TX[i] == -1) {
        cerr << W << " " << H << " " << N << endl;
        REP(j, N) cerr << b[j] << " " << k[j] << endl;
        REP(y, H) {
          REP(x, W) cerr << s[y][x] << " ";
          cerr << endl;
        }
        assert("bord is dissapeared" == "");
      }
      dfs(0);
      if (ans[0][0] == -1)
        throw DFSError();
      REP(y, H) {
        REP(x, W) {
          cout << ans[y][x];
          if (x != W - 1)
            cout << " ";
          else
            cout << endl;
        }
      }
    } catch (...) {
      cout << "NA" << endl;
    }
  }
  return 0;
}