Problem p02707 (C++)

Buggy submission (status: Runtime Error):
#include <bits/stdc++.h>

using namespace std;
typedef long long int ll;
typedef pair<ll, ll> P;
#define REP(i, n) for (ll i = 0LL; i < (ll)(n); i++)
#define REPR(i, n) for (ll i = n - 1; i > 0LL; i--)
#define FOR(i, n, m) for (ll i = n; i < (ll)(m); i++)
#define PRINT(x) cout << x << endl
#define ALL(v) v.begin(), v.end()
#define INF (ll)1e18
#define PI 3.14159265358979

ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }

ll MOD = 1000000007;

const int mod = 1000000007;
struct mint {
  ll x; // typedef long long ll;
  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;
  }

  // for prime mod
  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; }

int main() {
  ll N;
  cin >> N;
  vector<ll> A(N - 1);
  REP(i, N - 1) cin >> A[i];
  vector<ll> ans(N);
  REP(i, N) { ans[A[i] - 1] += 1; }
  REP(i, N) { PRINT(ans[i]); }
  return 0;
}


Fixed submission:
#include <bits/stdc++.h>

using namespace std;
typedef long long int ll;
typedef pair<ll, ll> P;
#define REP(i, n) for (ll i = 0LL; i < (ll)(n); i++)
#define REPR(i, n) for (ll i = n - 1; i > 0LL; i--)
#define FOR(i, n, m) for (ll i = n; i < (ll)(m); i++)
#define PRINT(x) cout << x << endl
#define ALL(v) v.begin(), v.end()
#define INF (ll)1e18
#define PI 3.14159265358979

ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
ll lcm(ll a, ll b) { return a / gcd(a, b) * b; }

ll MOD = 1000000007;

const int mod = 1000000007;
struct mint {
  ll x; // typedef long long ll;
  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;
  }

  // for prime mod
  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; }

int main() {
  ll N;
  cin >> N;
  vector<ll> A(N - 1);
  REP(i, N - 1) cin >> A[i];
  vector<ll> ans(N);
  REP(i, N - 1) { ans[A[i] - 1] += 1; }
  REP(i, N) { PRINT(ans[i]); }
  return 0;
}