Problem p00939 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>

#define _overload(_1, _2, _3, name, ...) name
#define _rep(i, n) _range(i, 0, n)
#define _range(i, a, b) for (int i = (int)(a); i < (int)(b); ++i)
#define rep(...) _overload(__VA_ARGS__, _range, _rep, )(__VA_ARGS__)

#define _rrep(i, n) _rrange(i, n, 0)
#define _rrange(i, a, b) for (int i = (int)(a)-1; i >= (int)(b); --i)
#define rrep(...) _overload(__VA_ARGS__, _rrange, _rrep, )(__VA_ARGS__)

#define _all(arg) begin(arg), end(arg)
#define uniq(arg) sort(_all(arg)), (arg).erase(unique(_all(arg)), end(arg))
#define getidx(ary, key) lower_bound(_all(ary), key) - begin(ary)
#define clr(a, b) memset((a), (b), sizeof(a))
#define bit(n) (1LL << (n))

// #define DEBUG

#ifdef DEBUG
#define dump(...) fprintf(stderr, __VA_ARGS__)
#else
#define dump(...)
#endif

template <class T> bool chmax(T &a, const T &b) {
  return (a < b) ? (a = b, 1) : 0;
}
template <class T> bool chmin(T &a, const T &b) {
  return (b < a) ? (a = b, 1) : 0;
}

using namespace std;
using ll = long long;
using vi = vector<int>;
using vll = vector<ll>;

const double EPS = 1e-10;
const double PI = acos(-1.0);
const ll inf = 1LL << 62;
const ll mod = 1000000007LL;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

ll extgcd(ll a, ll b, ll &x, ll &y) {
  x = 1, y = 0;
  ll g = a;
  if (b != 0)
    g = extgcd(b, a % b, y, x), y -= a / b * x;
  return g;
}
ll ADD(const ll &a, const ll &b, const ll &mod) { return (a + b) % mod; }
ll SUB(const ll &a, const ll &b, const ll &mod) { return (a - b + mod) % mod; }
ll MUL(const ll &a, const ll &b, const ll &mod) { return (1LL * a * b) % mod; }
ll DIV(const ll &a, const ll &b, const ll &mod) {
  ll x, y;
  extgcd(b, mod, x, y);
  return MUL(a, (x + mod) % mod, mod);
}

random_device rd;
mt19937 mt(rd());
uniform_int_distribution<int> dice(1, 6);
uniform_real_distribution<double> score(0.0, 10.0);

const int N = 15;
ll fact[N + 1];

void set_fact() {
  fact[0] = 1;
  rep(i, N) fact[i + 1] = ((ll)i + 1) * fact[i];
}

const int D = 10;
vi cnt(D);
int n;
string in;
ll inm, ins;

ll calc_parm() {
  int sum = 0;
  rep(i, D) sum += cnt[i];

  ll ret = fact[sum];
  rep(i, D) { ret /= fact[cnt[i]]; }

  return ret;
}

ll calc() {
  vi cnt_org = cnt;

  ll ret = 0LL;
  rep(i, n) {
    int num = in[i] - '0';

    rep(j, num) {
      if (cnt[j] <= 0)
        continue;
      cnt[j]--;
      ret += calc_parm();
      cnt[j]++;
    }

    if (cnt[num] <= 0)
      break;
    cnt[num]--;
  }

  cnt = cnt_org;

  return ret;
}

ll dfs(int num, int depth, ll mul, ll sum) {
  if (sum > ins)
    return 0LL;

  if (depth == n) {
    if (sum < ins)
      return calc_parm();
    if (sum == ins) {
      if (mul < inm)
        return calc_parm();
      if (mul == inm) {
        return calc();
      }
    }
    return 0LL;
  }

  ll ret = 0LL;
  rep(nnum, num, 10) {
    cnt[nnum]++;
    ret += dfs(nnum, depth + 1, mul * (nnum + 1), sum + nnum);
    cnt[nnum]--;
  }

  return ret;
}

int main(void) {
  cin >> in;
  n = in.size();

  set_fact();

  ins = 0LL, inm = 1LL;
  for (auto &c : in) {
    int e = c - '0';
    ins += e;
    inm *= (e + 1);
  }

  cout << dfs(0, 0, 1LL, 0LL) << endl;

  return 0;
}

Error: 0

Fixed submission:

#include <bits/stdc++.h>

#define _overload(_1, _2, _3, name, ...) name
#define _rep(i, n) _range(i, 0, n)
#define _range(i, a, b) for (int i = (int)(a); i < (int)(b); ++i)
#define rep(...) _overload(__VA_ARGS__, _range, _rep, )(__VA_ARGS__)

#define _rrep(i, n) _rrange(i, n, 0)
#define _rrange(i, a, b) for (int i = (int)(a)-1; i >= (int)(b); --i)
#define rrep(...) _overload(__VA_ARGS__, _rrange, _rrep, )(__VA_ARGS__)

#define _all(arg) begin(arg), end(arg)
#define uniq(arg) sort(_all(arg)), (arg).erase(unique(_all(arg)), end(arg))
#define getidx(ary, key) lower_bound(_all(ary), key) - begin(ary)
#define clr(a, b) memset((a), (b), sizeof(a))
#define bit(n) (1LL << (n))

// #define DEBUG

#ifdef DEBUG
#define dump(...) fprintf(stderr, __VA_ARGS__)
#else
#define dump(...)
#endif

template <class T> bool chmax(T &a, const T &b) {
  return (a < b) ? (a = b, 1) : 0;
}
template <class T> bool chmin(T &a, const T &b) {
  return (b < a) ? (a = b, 1) : 0;
}

using namespace std;
using ll = long long;
using vi = vector<int>;
using vll = vector<ll>;

const double EPS = 1e-10;
const double PI = acos(-1.0);
const ll inf = 1LL << 62;
const ll mod = 1000000007LL;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

ll extgcd(ll a, ll b, ll &x, ll &y) {
  x = 1, y = 0;
  ll g = a;
  if (b != 0)
    g = extgcd(b, a % b, y, x), y -= a / b * x;
  return g;
}
ll ADD(const ll &a, const ll &b, const ll &mod) { return (a + b) % mod; }
ll SUB(const ll &a, const ll &b, const ll &mod) { return (a - b + mod) % mod; }
ll MUL(const ll &a, const ll &b, const ll &mod) { return (1LL * a * b) % mod; }
ll DIV(const ll &a, const ll &b, const ll &mod) {
  ll x, y;
  extgcd(b, mod, x, y);
  return MUL(a, (x + mod) % mod, mod);
}

random_device rd;
mt19937 mt(rd());
uniform_int_distribution<int> dice(1, 6);
uniform_real_distribution<double> score(0.0, 10.0);

const int N = 15;
ll fact[N + 1];

void set_fact() {
  fact[0] = 1;
  rep(i, N) fact[i + 1] = ((ll)i + 1) * fact[i];
}

const int D = 10;
vi cnt;
int n;
string in;
ll inm, ins;

ll calc_parm() {
  int sum = 0;
  rep(i, D) sum += cnt[i];

  ll ret = fact[sum];
  rep(i, D) { ret /= fact[cnt[i]]; }

  return ret;
}

ll calc() {
  vi cnt_org = cnt;

  ll ret = 0LL;
  rep(i, n) {
    int num = in[i] - '0';

    rep(j, num) {
      cnt[j]--;
      ret += calc_parm();
      cnt[j]++;
    }

    if (cnt[num] <= 0)
      break;
    cnt[num]--;
  }

  cnt = cnt_org;

  return ret;
}

ll dfs(int num, int depth, ll mul, ll sum) {
  if (sum > ins)
    return 0LL;

  if (depth == n) {
    if (sum < ins)
      return calc_parm();
    if (sum == ins) {
      if (mul < inm)
        return calc_parm();
      if (mul == inm) {
        return calc();
      }
    }
    return 0LL;
  }

  ll ret = 0LL;
  rep(nnum, num, 10) {
    cnt[nnum]++;
    ret += dfs(nnum, depth + 1, mul * (nnum + 1), sum + nnum);
    cnt[nnum]--;
  }

  return ret;
}

int main(void) {
  in;
  cin >> in;
  n = in.size();

  cnt = vi(D);

  set_fact();

  ins = 0LL, inm = 1LL;
  for (auto &c : in) {
    int e = c - '0';
    ins += e;
    inm *= (e + 1);
  }

  cout << dfs(0, 0, 1LL, 0LL) << endl;

  return 0;
}