Problem p00493 (C++) — buggy submission, verdict: Memory Limit Exceeded

#define __USE_MINGW_ANSI_STDIO 0
#include <bits/stdc++.h>

using namespace std;
using ll = long long;
// #define int ll
using VI = vector<int>;
using VVI = vector<VI>;
using PII = pair<int, int>;

#define FOR(i, a, n) for (ll i = (ll)a; i < (ll)n; ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(x) x.begin(), x.end()
#define PB push_back

const ll LLINF = (1LL << 60);
const int INF = (1LL << 30);
const int MOD = 10000;

template <typename T> T &chmin(T &a, const T &b) { return a = min(a, b); }
template <typename T> T &chmax(T &a, const T &b) { return a = max(a, b); }
template <typename T> bool IN(T a, T b, T x) { return a <= x && x < b; }
template <typename T> T ceil(T a, T b) { return a / b + !!(a % b); }
template <class S, class T>
ostream &operator<<(ostream &out, const pair<S, T> &a) {
  out << '(' << a.first << ',' << a.second << ')';
  return out;
}
template <class T> ostream &operator<<(ostream &out, const vector<T> &a) {
  out << '[';
  REP(i, a.size()) {
    out << a[i];
    if (i != a.size() - 1)
      out << ',';
  }
  out << ']';
  return out;
}

int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0};

int dp[505][2][505][10][3][3];
signed main(void) {
  cin.tie(0);
  ios::sync_with_stdio(false);

  string a, b;
  int m;
  cin >> a >> b >> m;

  int n = b.size();
  if (n != 1) {
    VI mo(n);
    mo[0] = 1 % m;
    FOR(i, 1, n) mo[i] = mo[i - 1] * 10 % m;
    // N以下の数を求める桁DP
    dp[0][0][0][0][0][0] = 1;
    REP(i, n) REP(j, 2) REP(k, m) REP(l, 10) REP(x, 3) REP(y, 3) {
      if (!dp[i][j][k][l][x][y])
        continue;
      // cout << i << "," << j << "," << k << "," << l << "," << x << "," << y
      // << " "; cout << dp[i][j][k][l][x][y] << endl;
      int lim = j ? 9 : b[i] - '0';
      REP(d, lim + 1) {
        int cond = 0;
        if (y == 1) {
          if (l < d)
            cond = 1;
          else if (l > d)
            cond = 2;
        } else if (x == 1) {
          if (l > d)
            cond = 2;
        } else if (x == 2) {
          if (l < d)
            cond = 1;
        }
        int cond2 = 0;
        if (y == 0) {
          if (d)
            cond2 = 1;
        } else if (y == 1) {
          cond2 = 2;
        } else {
          cond2 = 2;
        }
        (dp[i + 1][j || d < lim][(k + mo[n - 1 - i] * d) % m][d][cond][cond2] +=
         dp[i][j][k][l][x][y]) %= MOD;
      }
    }
  }

  int ans = 0;
  if (n != 1) {
    REP(i, 2) REP(j, 10) FOR(k, 1, 3) REP(l, 3) {
      if (!dp[n][i][0][j][k][l])
        continue;
      // cout << n << "," << i << "," << 0 << "," << j << "," << k << "," << l
      // << " "; cout << dp[n][i][0][j][k][l] << endl;
      (ans += dp[n][i][0][j][k][l]) %= MOD;
    }
    REP(i, 9) { ans += (i + 1) % m == 0; }
  } else {
    REP(i, b[0] - '0') { ans += (i + 1) % m == 0; }
  }

  // cout << ans << endl;

  n = a.size();
  if (n != 1) {
    VI mo(n);
    mo[0] = 1 % m;
    FOR(i, 1, n) mo[i] = mo[i - 1] * 10 % m;
    // N以下の数を求める桁DP
    memset(dp, 0, sizeof(dp));
    dp[0][0][0][0][0][0] = 1;
    REP(i, n) REP(j, 2) REP(k, m) REP(l, 10) REP(x, 3) REP(y, 3) {
      if (!dp[i][j][k][l][x][y])
        continue;
      // cout << i << "," << j << "," << k << "," << l << "," << x << "," << y
      // << " "; cout << dp[i][j][k][l][x][y] << endl;
      int lim = j ? 9 : a[i] - '0';
      REP(d, lim + 1) {
        int cond = 0;
        if (y == 1) {
          if (l < d)
            cond = 1;
          else if (l > d)
            cond = 2;
        } else if (x == 1) {
          if (l > d)
            cond = 2;
        } else if (x == 2) {
          if (l < d)
            cond = 1;
        }
        int cond2 = 0;
        if (y == 0) {
          if (d)
            cond2 = 1;
        } else if (y == 1) {
          cond2 = 2;
        } else {
          cond2 = 2;
        }
        (dp[i + 1][j || d < lim][(k + mo[n - 1 - i] * d) % m][d][cond][cond2] +=
         dp[i][j][k][l][x][y]) %= MOD;
      }
    }
  }

  if (n != 1) {
    REP(i, 2) REP(j, 10) FOR(k, 1, 3) REP(l, 3) {
      if (!dp[n][i][0][j][k][l])
        continue;
      // cout << n << "," << i << "," << 0 << "," << j << "," << k << "," << l
      // << " "; cout << dp[n][i][0][j][k][l] << endl;
      (ans -= dp[n][i][0][j][k][l] + MOD) %= MOD;
    }
    REP(i, 9) ans -= (i + 1) % m == 0;
    ans = (ans % MOD + MOD) % MOD;
  } else {
    REP(i, a[0] - '0') { ans -= (i + 1) % m == 0; }
  }

  // aがmの倍数かつジグザグ数ならansに+1する
  bool can = a[0] != a[1];
  bool flag = a[0] < a[1];
  FOR(i, 2, n) {
    if (flag) {
      if (a[i - 1] > a[i]) {
        flag = false;
      } else {
        can = false;
        break;
      }
    } else {
      if (a[i - 1] < a[i]) {
        flag = true;
      } else {
        can = false;
        break;
      }
    }
  }
  int now = 0;
  for (int i = n - 1; i >= 0; --i)
    now = (now * 10 + (a[i] - '0')) % m;
  if (now)
    can = false;
  if (can)
    ans++;

  cout << ans % MOD << endl;

  return 0;
}


Error: MLE

Fixed submission:

#define __USE_MINGW_ANSI_STDIO 0
#include <bits/stdc++.h>

using namespace std;
using ll = long long;
#define int ll
using VI = vector<int>;
using VVI = vector<VI>;
using PII = pair<int, int>;

#define FOR(i, a, n) for (ll i = (ll)a; i < (ll)n; ++i)
#define REP(i, n) FOR(i, 0, n)
#define ALL(x) x.begin(), x.end()
#define PB push_back

const ll LLINF = (1LL << 60);
const int INF = (1LL << 30);
const int MOD = 10000;

template <typename T> T &chmin(T &a, const T &b) { return a = min(a, b); }
template <typename T> T &chmax(T &a, const T &b) { return a = max(a, b); }
template <typename T> bool IN(T a, T b, T x) { return a <= x && x < b; }
template <typename T> T ceil(T a, T b) { return a / b + !!(a % b); }
template <class S, class T>
ostream &operator<<(ostream &out, const pair<S, T> &a) {
  out << '(' << a.first << ',' << a.second << ')';
  return out;
}
template <class T> ostream &operator<<(ostream &out, const vector<T> &a) {
  out << '[';
  REP(i, a.size()) {
    out << a[i];
    if (i != a.size() - 1)
      out << ',';
  }
  out << ']';
  return out;
}

int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0};

int dp[505][2][505][10][3][3];
signed main(void) {
  cin.tie(0);
  ios::sync_with_stdio(false);

  string a, b;
  int m;
  cin >> a >> b >> m;

  int n = b.size();
  if (n != 1) {
    VI mo(n);
    mo[0] = 1 % m;
    FOR(i, 1, n) mo[i] = mo[i - 1] * 10 % m;
    // N以下の数を求める桁DP
    dp[0][0][0][0][0][0] = 1;
    REP(i, n) REP(j, 2) REP(k, m) REP(l, 10) REP(x, 3) REP(y, 3) {
      if (!dp[i][j][k][l][x][y])
        continue;
      // cout << i << "," << j << "," << k << "," << l << "," << x << "," << y
      // << " "; cout << dp[i][j][k][l][x][y] << endl;
      int lim = j ? 9 : b[i] - '0';
      REP(d, lim + 1) {
        int cond = 0;
        if (y == 1) {
          if (l < d)
            cond = 1;
          else if (l > d)
            cond = 2;
        } else if (x == 1) {
          if (l > d)
            cond = 2;
        } else if (x == 2) {
          if (l < d)
            cond = 1;
        }
        int cond2 = 0;
        if (y == 0) {
          if (d)
            cond2 = 1;
        } else if (y == 1) {
          cond2 = 2;
        } else {
          cond2 = 2;
        }
        (dp[i + 1][j || d < lim][(k + mo[n - 1 - i] * d) % m][d][cond][cond2] +=
         dp[i][j][k][l][x][y]) %= MOD;
      }
    }
  }

  int ans = 0;
  if (n != 1) {
    REP(i, 2) REP(j, 10) FOR(k, 1, 3) REP(l, 3) {
      if (!dp[n][i][0][j][k][l])
        continue;
      // cout << n << "," << i << "," << 0 << "," << j << "," << k << "," << l
      // << " "; cout << dp[n][i][0][j][k][l] << endl;
      (ans += dp[n][i][0][j][k][l]) %= MOD;
    }
    REP(i, 9) { ans += (i + 1) % m == 0; }
  } else {
    REP(i, b[0] - '0') { ans += (i + 1) % m == 0; }
  }

  // cout << ans << endl;

  n = a.size();
  if (n != 1) {
    VI mo(n);
    mo[0] = 1 % m;
    FOR(i, 1, n) mo[i] = mo[i - 1] * 10 % m;
    // N以下の数を求める桁DP
    memset(dp, 0, sizeof(dp));
    dp[0][0][0][0][0][0] = 1;
    REP(i, n) REP(j, 2) REP(k, m) REP(l, 10) REP(x, 3) REP(y, 3) {
      if (!dp[i][j][k][l][x][y])
        continue;
      // cout << i << "," << j << "," << k << "," << l << "," << x << "," << y
      // << " "; cout << dp[i][j][k][l][x][y] << endl;
      int lim = j ? 9 : a[i] - '0';
      REP(d, lim + 1) {
        int cond = 0;
        if (y == 1) {
          if (l < d)
            cond = 1;
          else if (l > d)
            cond = 2;
        } else if (x == 1) {
          if (l > d)
            cond = 2;
        } else if (x == 2) {
          if (l < d)
            cond = 1;
        }
        int cond2 = 0;
        if (y == 0) {
          if (d)
            cond2 = 1;
        } else if (y == 1) {
          cond2 = 2;
        } else {
          cond2 = 2;
        }
        (dp[i + 1][j || d < lim][(k + mo[n - 1 - i] * d) % m][d][cond][cond2] +=
         dp[i][j][k][l][x][y]) %= MOD;
      }
    }
  }

  if (n != 1) {
    REP(i, 2) REP(j, 10) FOR(k, 1, 3) REP(l, 3) {
      if (!dp[n][i][0][j][k][l])
        continue;
      // cout << n << "," << i << "," << 0 << "," << j << "," << k << "," << l
      // << " "; cout << dp[n][i][0][j][k][l] << endl;
      (ans -= dp[n][i][0][j][k][l]) %= MOD;
    }
    REP(i, 9) ans -= (i + 1) % m == 0;
  } else {
    REP(i, a[0] - '0') { ans -= (i + 1) % m == 0; }
  }

  // aがmの倍数かつジグザグ数ならansに+1する
  bool can = a[0] != a[1];
  bool flag = a[0] < a[1];
  FOR(i, 2, n) {
    if (flag) {
      if (a[i - 1] > a[i]) {
        flag = false;
      } else {
        can = false;
        break;
      }
    } else {
      if (a[i - 1] < a[i]) {
        flag = true;
      } else {
        can = false;
        break;
      }
    }
  }
  int now = 0;
  for (int i = n - 1; i >= 0; --i)
    now = (now * 10 + (a[i] - '0')) % m;
  if (now)
    can = false;
  if (can)
    ans++;

  cout << ans << endl;

  return 0;
}