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

#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < n; i++)
#define rep2(i, a, n) for (int i = a; i < n; i++)
#define been(ix) (ix).begin(), (ix).end()
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<long long> vl;
const ll INFL = 1e18;
const int INF = 1001001001;
typedef pair<int, int> P;
#define foreach(ix, i) for (auto &(ix) : (i))
typedef long double ld;
int mod = 1000000007;
const double PI = acos(-1);
struct mint {
  ll x;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  mint operator-() const { return mint(-x); }
  mint &operator+=(const mint a) {
    if ((x += a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator-=(const mint a) {
    if ((x += mod - a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const { return mint(*this) += a; }
  mint operator-(const mint a) const { return mint(*this) -= a; }
  mint operator*(const mint a) const { return mint(*this) *= a; }
  mint pow(ll t) const {
    if (!t)
      return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1)
      a *= *this;
    return a;
  }
  mint inv() const { return pow(mod - 2); }
  mint &operator/=(const mint a) { return *this *= a.inv(); }
  mint operator/(const mint a) const { return mint(*this) /= a; }
};
istream &operator>>(istream &is, const mint &a) { return is >> a.x; }
ostream &operator<<(ostream &os, const mint &a) { return os << a.x; }
struct combination {
  vector<mint> fact, ifact;
  combination(int n) : fact(n + 1), ifact(n + 1) {
    assert(n < mod);
    fact[0] = 1;
    for (int i = 1; i <= n; ++i)
      fact[i] = fact[i - 1] * i;
    ifact[n] = fact[n].inv();
    for (int i = n; i >= 1; --i)
      ifact[i - 1] = ifact[i] * i;
  }
  mint operator()(int n, int k) {
    if (k < 0 || k > n)
      return 0;
    return fact[n] * ifact[k] * ifact[n - k];
  }
} com(200005);
mint choose(int n, int a) {
  mint x = 1, y = 1;
  rep(i, a) {
    x *= n - i;
    y *= i + 1;
  }
  return x / y;
}
int main() {
  ll n;
  cin >> n;
  string s;
  cin >> s;
  ll fcnt = 0;
  mint sumu = 0, sumt = 0;
  reverse(been(s));
  rep(i, n) {
    if (s[i] == '1') {
      fcnt++;
    }
  }
  mint z = 2;
  if (fcnt != 1 && fcnt != 0) {
    mod = fcnt - 1;
    rep(i, n) {
      mint x;
      if (s[i] == '1') {
        // x=pow(2,i);
        sumu += z.pow(i);
      }
    }
  }
  mod = fcnt + 1;
  rep(i, n) {
    mint x;
    if (s[i] == '1') {
      // x=pow(2,i);
      sumt += z.pow(i);
    }
  }
  vi res(n, 0);
  rep(i, n) {
    ll ans = 1;
    if (s[i] == '0') {
      mod = fcnt + 1;
      ll th = (sumt + z.pow(i)).x;
      while (th != 0) {
        ans++;
        ll x = __builtin_popcount(th);
        th %= x;
      }
      res[i] = ans;
    } else {
      if (fcnt != 0 && fcnt != 1) {
        mod = fcnt - 1;
        // mint z=2;
        ll th = (sumu - z.pow(i)).x;
        while (th != 0) {
          ans++;
          ll x = __builtin_popcount(th);
          th %= x;
        }
        res[i] = ans;
      }
    }
  }
  reverse(been(res));
  rep(i, n) cout << res[i] << endl;
}

Error: 0

Fixed submission:

#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < n; i++)
#define rep2(i, a, n) for (int i = a; i < n; i++)
#define been(ix) (ix).begin(), (ix).end()
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<long long> vl;
const ll INFL = 1e18;
const int INF = 1001001001;
typedef pair<int, int> P;
#define foreach(ix, i) for (auto &(ix) : (i))
typedef long double ld;
int mod = 1000000007;
const double PI = acos(-1);
struct mint {
  ll x;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  mint operator-() const { return mint(-x); }
  mint &operator+=(const mint a) {
    if ((x += a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator-=(const mint a) {
    if ((x += mod - a.x) >= mod)
      x -= mod;
    return *this;
  }
  mint &operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const { return mint(*this) += a; }
  mint operator-(const mint a) const { return mint(*this) -= a; }
  mint operator*(const mint a) const { return mint(*this) *= a; }
  mint pow(ll t) const {
    if (!t)
      return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1)
      a *= *this;
    return a;
  }
  mint inv() const { return pow(mod - 2); }
  mint &operator/=(const mint a) { return *this *= a.inv(); }
  mint operator/(const mint a) const { return mint(*this) /= a; }
};
istream &operator>>(istream &is, const mint &a) { return is >> a.x; }
ostream &operator<<(ostream &os, const mint &a) { return os << a.x; }
struct combination {
  vector<mint> fact, ifact;
  combination(int n) : fact(n + 1), ifact(n + 1) {
    assert(n < mod);
    fact[0] = 1;
    for (int i = 1; i <= n; ++i)
      fact[i] = fact[i - 1] * i;
    ifact[n] = fact[n].inv();
    for (int i = n; i >= 1; --i)
      ifact[i - 1] = ifact[i] * i;
  }
  mint operator()(int n, int k) {
    if (k < 0 || k > n)
      return 0;
    return fact[n] * ifact[k] * ifact[n - k];
  }
} com(200005);
mint choose(int n, int a) {
  mint x = 1, y = 1;
  rep(i, a) {
    x *= n - i;
    y *= i + 1;
  }
  return x / y;
}
int main() {
  ll n;
  cin >> n;
  string s;
  cin >> s;
  ll fcnt = 0;
  mint sumu = 0, sumt = 0;
  reverse(been(s));
  rep(i, n) {
    if (s[i] == '1') {
      fcnt++;
    }
  }
  mod = fcnt - 1;
  mint z = 2;
  rep(i, n) {
    mint x;
    if (s[i] == '1') {
      // x=pow(2,i);
      sumu += z.pow(i);
    }
  }
  mod = fcnt + 1;
  rep(i, n) {
    mint x;
    if (s[i] == '1') {
      // x=pow(2,i);
      sumt += z.pow(i);
    }
  }
  vi res(n);
  rep(i, n) {
    ll ans = 1;
    if (s[i] == '0') {
      mod = fcnt + 1;
      ll th = (sumt + z.pow(i)).x;
      while (th != 0) {
        ans++;
        ll x = __builtin_popcount(th);
        th %= x;
      }
      res[i] = ans;
    } else {
      mod = fcnt - 1;
      // mint z=2;
      ll th = (sumu - z.pow(i)).x;
      while (th != 0) {
        ans++;
        ll x = __builtin_popcount(th);
        th %= x;
      }
      res[i] = ans;
    }
  }
  reverse(been(res));
  rep(i, n) cout << res[i] << endl;
}