Problem p02609 (C++) — buggy submission, verdict: Runtime Error

#include <bits/stdc++.h>
using namespace std;
/*******  All Required define Pre-Processors and typedef Constants *******/
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.rbegin(), cont.rend()
#define Dcout(a) cout << setprecision(20) << a << endl
#define ll long long
#define ld long double
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pb push_back
#define eb emplace_back
#define vi vector<int>
#define vll vector<ll>
#define vpi vector<pii>
#define vpll vector<pll>
#define fi first
#define se second
using Graph = vector<vector<ll>>;
// const ll INF = (1LL << 60);
const double pi = acos(-1.0);
/******************* debug ********************/
#define debug(var)                                                             \\
  do {                                                                         \\
    std::cout << #var << " : ";                                                \\
    view(var);                                                                 \\
  } while (0)
#define deb cout << "line : " << __LINE__ << " debug" << endl
template <typename T> void view(T e) { cout << e << endl; }
template <typename T> void view(const vector<T> &v) {
  for (const auto &e : v)
    cout << e << " ";
  cout << endl;
}
template <typename T> void view(const vector<vector<T>> &vv) {
  for (const auto &v : vv) {
    view(v);
  }
}
/****** Template of some basic operations *****/
struct IoSetup {
  IoSetup() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(10);
    cerr << fixed << setprecision(10);
  }
} iosetup;

template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
  os << p.first << " " << p.second;
  return os;
}

template <typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) {
  is >> p.first >> p.second;
  return is;
}

template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
  for (int i = 0; i < (int)v.size(); i++) {
    os << v[i] << (i + 1 != v.size() ? " " : "");
  }
  return os;
}

template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (T &in : v)
    is >> in;
  return is;
}

template <typename T1, typename T2> inline bool chmax(T1 &a, T2 b) {
  return a < b && (a = b, true);
}

template <typename T1, typename T2> inline bool chmin(T1 &a, T2 b) {
  return a > b && (a = b, true);
}

template <typename T = ll> vector<T> make_v(size_t a) { return vector<T>(a); }

template <typename T, typename... Ts> auto make_v(size_t a, Ts... ts) {
  return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}

template <typename T, typename V>
typename enable_if<is_class<T>::value == 0>::type fill_v(T &t, const V &v) {
  t = v;
}

template <typename T, typename V>
typename enable_if<is_class<T>::value != 0>::type fill_v(T &t, const V &v) {
  for (auto &e : t)
    fill_v(e, v);
}

template <typename F> struct FixPoint : F {
  FixPoint(F &&f) : F(forward<F>(f)) {}

  template <typename... Args> decltype(auto) operator()(Args &&...args) const {
    return F::operator()(*this, forward<Args>(args)...);
  }
};

template <typename F> inline decltype(auto) MFP(F &&f) {
  return FixPoint<F>{forward<F>(f)};
}
/*******************************************************/
/******************** Start coding ! *******************/
int pcnt(int x) { return __builtin_popcount(x); }

int f(int x) {
  if (x == 0)
    return 0;
  return f(x % pcnt(x)) + 1;
}

int main() {
  int n;
  cin >> n;
  string s;
  cin >> s;
  vector<int> x(n);
  rep(i, n) x[i] = s[i] - '0';

  // xのpopcount
  int pc = 0;
  rep(i, n) pc += x[i];
  // 出力用
  vector<int> ans(n);
  rep(b, 2) {
    int npc = pc;
    // 元のビットが0の場合は1に変わるのでnpc++, 1の場合は0になるのでnpc--
    if (b == 0)
      npc++;
    else
      npc--;
    // 0で割ってしまうのを避ける
    if (npc <= 0)
      continue;

    // 元の割った余りを求める。
    int r0 = 0;
    rep(i, n) {
      // ２進数なので位をあげは*2で
      // 一番したの位を加算
      r0 = (r0 * 2) % npc;
      r0 += x[i];
    }
    int k = 1;
    for (int i = n - 1; i >= 0; i--) {
      if (x[i] == b) {
        int r = r0;
        // 0->1のときはkをたす必要がある, 1->0は引くけれどマイナスに注意
        if (b == 0)
          r = (r + k) % npc;
        else
          r = (r - k + npc) % npc;
        ans[i] = f(r) + 1;
      }

      // k=2^i
      k = (k * 2) % npc;
    }
  }

  rep(i, n) cout << ans[i] << endl;
}


Error: 0

Fixed submission:

#include <bits/stdc++.h>
using namespace std;
/*******  All Required define Pre-Processors and typedef Constants *******/
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.rbegin(), cont.rend()
#define Dcout(a) cout << setprecision(20) << a << endl
#define ll long long
#define ld long double
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pb push_back
#define eb emplace_back
#define vi vector<int>
#define vll vector<ll>
#define vpi vector<pii>
#define vpll vector<pll>
#define fi first
#define se second
using Graph = vector<vector<ll>>;
// const ll INF = (1LL << 60);
const double pi = acos(-1.0);
/******************* debug ********************/
#define debug(var)                                                             \\
  do {                                                                         \\
    std::cout << #var << " : ";                                                \\
    view(var);                                                                 \\
  } while (0)
#define deb cout << "line : " << __LINE__ << " debug" << endl
template <typename T> void view(T e) { cout << e << endl; }
template <typename T> void view(const vector<T> &v) {
  for (const auto &e : v)
    cout << e << " ";
  cout << endl;
}
template <typename T> void view(const vector<vector<T>> &vv) {
  for (const auto &v : vv) {
    view(v);
  }
}
/****** Template of some basic operations *****/
struct IoSetup {
  IoSetup() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(10);
    cerr << fixed << setprecision(10);
  }
} iosetup;

template <typename T1, typename T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &p) {
  os << p.first << " " << p.second;
  return os;
}

template <typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) {
  is >> p.first >> p.second;
  return is;
}

template <typename T> ostream &operator<<(ostream &os, const vector<T> &v) {
  for (int i = 0; i < (int)v.size(); i++) {
    os << v[i] << (i + 1 != v.size() ? " " : "");
  }
  return os;
}

template <typename T> istream &operator>>(istream &is, vector<T> &v) {
  for (T &in : v)
    is >> in;
  return is;
}

template <typename T1, typename T2> inline bool chmax(T1 &a, T2 b) {
  return a < b && (a = b, true);
}

template <typename T1, typename T2> inline bool chmin(T1 &a, T2 b) {
  return a > b && (a = b, true);
}

template <typename T = ll> vector<T> make_v(size_t a) { return vector<T>(a); }

template <typename T, typename... Ts> auto make_v(size_t a, Ts... ts) {
  return vector<decltype(make_v<T>(ts...))>(a, make_v<T>(ts...));
}

template <typename T, typename V>
typename enable_if<is_class<T>::value == 0>::type fill_v(T &t, const V &v) {
  t = v;
}

template <typename T, typename V>
typename enable_if<is_class<T>::value != 0>::type fill_v(T &t, const V &v) {
  for (auto &e : t)
    fill_v(e, v);
}

template <typename F> struct FixPoint : F {
  FixPoint(F &&f) : F(forward<F>(f)) {}

  template <typename... Args> decltype(auto) operator()(Args &&...args) const {
    return F::operator()(*this, forward<Args>(args)...);
  }
};

template <typename F> inline decltype(auto) MFP(F &&f) {
  return FixPoint<F>{forward<F>(f)};
}
/*******************************************************/
/******************** Start coding ! *******************/

ll f(ll n) {
  ll ret = 1;
  while (n % __builtin_popcount(n) != 0) {
    ret++;
    n = n % __builtin_popcount(n);
  }

  return ret;
}

int main() {
  int n;
  cin >> n;
  string x;
  cin >> x;
  rep(i, n) {
    string s = x;
    if (s[i] == '0')
      s[i] = '1';
    else
      s[i] = '0';
    ll num = stoll(s, 0, 2);
    cout << f(num) << endl;
  }
}