Problem p03835 (C++)

Buggy submission (status: Time Limit Exceeded):
#pragma GCC target("avx2")
#pragma GCC optimization("O3")
#pragma GCC optimization("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define double long double
#define fo(a, b) for (int a = 0; a < b; a++)
#define Sort(a) sort(a.begin(), a.end())
#define rev(a) reverse(a.begin(), a.end())
#define fi first
#define se second
#define sz size()
#define bgn begin()
#define en end()
#define pb push_back
#define pp() pop_back()
#define V vector
#define P pair
#define yuko(a) setprecision(a)
#define uni(a) a.erase(unique(a.begin(), a.end()), a.end())
#define Q queue
#define pri priority_queue
#define Pri priority_queue<int, vector<int>, greater<int>>
#define PriP                                                                   \
  priority_queue<P<int, int>, vector<P<int, int>>, greater<P<int, int>>>
#define ff first.first
#define fs first.second
#define sf second.first
#define ss second.second
#define all(a) (a).begin(), (a).end()
#define elif else if
int low(V<int> &a, int b) {
  auto c = lower_bound(a.begin(), a.end(), b);
  int d = c - a.bgn;
  return d;
}
int upp(V<int> &a, int b) {
  auto c = upper_bound(a.begin(), a.end(), b);
  int d = c - a.bgn;
  return d;
}
template <class T> void cou(vector<vector<T>> a) {
  int b = a.size();
  int c = a[0].size();
  fo(i, b) {
    fo(j, c) {
      cout << a[i][j];
      if (j == c - 1)
        cout << endl;
      else
        cout << ' ';
    }
  }
}
int wari(int a, int b) {
  if (a % b == 0)
    return a / b;
  else
    return a / b + 1;
}
int keta(int a) {
  double b = a;
  b = log10(b);
  int c = b;
  return c + 1;
}
int souwa(int a) { return a * (a + 1) / 2; }
int gcm(int a, int b) {
  if (a % b == 0)
    return b;
  return gcm(b, a % b);
}
bool prime(int a) {
  if (a < 2)
    return false;
  else if (a == 2)
    return true;
  else if (a % 2 == 0)
    return false;
  for (int i = 3; i <= sqrt(a) + 1; i += 2) {
    if (a % i == 0)
      return false;
  }
  return true;
}
struct Union {
  vector<int> par;
  Union(int a) { par = vector<int>(a, -1); }
  int find(int a) {
    if (par[a] < 0)
      return a;
    else
      return par[a] = find(par[a]);
  }
  bool same(int a, int b) { return find(a) == find(b); }
  int Size(int a) { return -par[find(a)]; }
  void unite(int a, int b) {
    a = find(a);
    b = find(b);
    if (a == b)
      return;
    if (Size(b) > Size(a))
      swap<int>(a, b);
    par[a] += par[b];
    par[b] = a;
  }
};
int ketas(int a) {
  string b = to_string(a);
  int c = 0;
  fo(i, keta(a)) { c += b[i] - '0'; }
  return c;
}
bool fe(int a, int b) {
  a %= 10;
  b %= 10;
  if (a == 0)
    a = 10;
  if (b == 0)
    b = 10;
  if (a > b)
    return true;
  else
    return false;
}
int INF = 1000000007;
struct edge {
  int s, t, d;
};
V<int> mojisyu(string a) {
  V<int> b(26, 0);
  fo(i, a.sz) { b[a[i] - 'a']++; }
  return b;
}
int wa2(int a) {
  if (a % 2 == 1)
    return a / 2;
  return a / 2 - 1;
}
int kaijou(int a) {
  int b = 1;
  fo(i, a) b *= i + 1;
  return b;
}
long long modpow(long long a, long long n, long long mod) {
  long long res = 1;
  while (n > 0) {
    if (n & 1)
      res = res * a % mod;
    a = a * a % mod;
    n >>= 1;
  }
  return res;
}
// a^{-1} mod を計算する
long long modinv(long long a, long long mod) { return modpow(a, mod - 2, mod); }

int lcm(int a, int b) {
  int c = modinv(gcm(a, b), INF);
  return ((a * c) % INF) * (b % INF) % INF;
}
int lcm_kai(int a, int b) {
  if (a < b)
    swap(a, b);
  int n = a, m = b;
  while (a % b != 0) {
    int t = b;
    b = a % b;
    a = t;
  }
  return n / b * m;
}
int MOD = INF;
int fac[1000010], finv[1000010], inv[1000010];

void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < 1000010; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}
// 二項係数計算
int COM(int n, int k) {
  if (n < k)
    return 0;
  if (n < 0 || k < 0)
    return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

int pow_kai(int a, int b) {
  int c = 1;
  while (b > 0) { // bit全部捨てるまで
    if (b % 2) {  // 一番右のbitが1
      c = c * a;
    }
    a = a * a;
    b >>= 1; // 全体右に1つシフト
  }
  return c;
}
// 12だったら{(2,2),(3,1)}って返してくれるはず
V<P<int, int>> factorize(int n) {
  V<P<int, int>> res;
  for (int i = 2; i * i <= n; i++) {
    if (n % i)
      continue;
    res.emplace_back(i, 0);
    while (n % i == 0) {
      n /= i;
      res.back().second++;
    }
  }
  if (n != 1)
    res.emplace_back(n, 1);
  return res;
}
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

signed main() {
  int k, s;
  cin >> k >> s;
  int ans = 0;
  for (int i = 0; i <= k; ++i) {
    for (int j = 0; j <= k; ++j) {
      for (int l = 0; l <= k; ++l) {
        if (i + j + l == s)
          ans++;
      }
    }
  }
  cout << ans << endl;
}

Fixed submission:
#pragma GCC target("avx2")
#pragma GCC optimization("O3")
#pragma GCC optimization("unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define int long long
#define double long double
#define fo(a, b) for (int a = 0; a < b; a++)
#define Sort(a) sort(a.begin(), a.end())
#define rev(a) reverse(a.begin(), a.end())
#define fi first
#define se second
#define sz size()
#define bgn begin()
#define en end()
#define pb push_back
#define pp() pop_back()
#define V vector
#define P pair
#define yuko(a) setprecision(a)
#define uni(a) a.erase(unique(a.begin(), a.end()), a.end())
#define Q queue
#define pri priority_queue
#define Pri priority_queue<int, vector<int>, greater<int>>
#define PriP                                                                   \
  priority_queue<P<int, int>, vector<P<int, int>>, greater<P<int, int>>>
#define ff first.first
#define fs first.second
#define sf second.first
#define ss second.second
#define all(a) (a).begin(), (a).end()
#define elif else if
int low(V<int> &a, int b) {
  auto c = lower_bound(a.begin(), a.end(), b);
  int d = c - a.bgn;
  return d;
}
int upp(V<int> &a, int b) {
  auto c = upper_bound(a.begin(), a.end(), b);
  int d = c - a.bgn;
  return d;
}
template <class T> void cou(vector<vector<T>> a) {
  int b = a.size();
  int c = a[0].size();
  fo(i, b) {
    fo(j, c) {
      cout << a[i][j];
      if (j == c - 1)
        cout << endl;
      else
        cout << ' ';
    }
  }
}
int wari(int a, int b) {
  if (a % b == 0)
    return a / b;
  else
    return a / b + 1;
}
int keta(int a) {
  double b = a;
  b = log10(b);
  int c = b;
  return c + 1;
}
int souwa(int a) { return a * (a + 1) / 2; }
int gcm(int a, int b) {
  if (a % b == 0)
    return b;
  return gcm(b, a % b);
}
bool prime(int a) {
  if (a < 2)
    return false;
  else if (a == 2)
    return true;
  else if (a % 2 == 0)
    return false;
  for (int i = 3; i <= sqrt(a) + 1; i += 2) {
    if (a % i == 0)
      return false;
  }
  return true;
}
struct Union {
  vector<int> par;
  Union(int a) { par = vector<int>(a, -1); }
  int find(int a) {
    if (par[a] < 0)
      return a;
    else
      return par[a] = find(par[a]);
  }
  bool same(int a, int b) { return find(a) == find(b); }
  int Size(int a) { return -par[find(a)]; }
  void unite(int a, int b) {
    a = find(a);
    b = find(b);
    if (a == b)
      return;
    if (Size(b) > Size(a))
      swap<int>(a, b);
    par[a] += par[b];
    par[b] = a;
  }
};
int ketas(int a) {
  string b = to_string(a);
  int c = 0;
  fo(i, keta(a)) { c += b[i] - '0'; }
  return c;
}
bool fe(int a, int b) {
  a %= 10;
  b %= 10;
  if (a == 0)
    a = 10;
  if (b == 0)
    b = 10;
  if (a > b)
    return true;
  else
    return false;
}
int INF = 1000000007;
struct edge {
  int s, t, d;
};
V<int> mojisyu(string a) {
  V<int> b(26, 0);
  fo(i, a.sz) { b[a[i] - 'a']++; }
  return b;
}
int wa2(int a) {
  if (a % 2 == 1)
    return a / 2;
  return a / 2 - 1;
}
int kaijou(int a) {
  int b = 1;
  fo(i, a) b *= i + 1;
  return b;
}
long long modpow(long long a, long long n, long long mod) {
  long long res = 1;
  while (n > 0) {
    if (n & 1)
      res = res * a % mod;
    a = a * a % mod;
    n >>= 1;
  }
  return res;
}
// a^{-1} mod を計算する
long long modinv(long long a, long long mod) { return modpow(a, mod - 2, mod); }

int lcm(int a, int b) {
  int c = modinv(gcm(a, b), INF);
  return ((a * c) % INF) * (b % INF) % INF;
}
int lcm_kai(int a, int b) {
  if (a < b)
    swap(a, b);
  int n = a, m = b;
  while (a % b != 0) {
    int t = b;
    b = a % b;
    a = t;
  }
  return n / b * m;
}
int MOD = INF;
int fac[1000010], finv[1000010], inv[1000010];

void COMinit() {
  fac[0] = fac[1] = 1;
  finv[0] = finv[1] = 1;
  inv[1] = 1;
  for (int i = 2; i < 1000010; i++) {
    fac[i] = fac[i - 1] * i % MOD;
    inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
    finv[i] = finv[i - 1] * inv[i] % MOD;
  }
}
// 二項係数計算
int COM(int n, int k) {
  if (n < k)
    return 0;
  if (n < 0 || k < 0)
    return 0;
  return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
}

int pow_kai(int a, int b) {
  int c = 1;
  while (b > 0) { // bit全部捨てるまで
    if (b % 2) {  // 一番右のbitが1
      c = c * a;
    }
    a = a * a;
    b >>= 1; // 全体右に1つシフト
  }
  return c;
}
// 12だったら{(2,2),(3,1)}って返してくれるはず
V<P<int, int>> factorize(int n) {
  V<P<int, int>> res;
  for (int i = 2; i * i <= n; i++) {
    if (n % i)
      continue;
    res.emplace_back(i, 0);
    while (n % i == 0) {
      n /= i;
      res.back().second++;
    }
  }
  if (n != 1)
    res.emplace_back(n, 1);
  return res;
}
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};

signed main() {
  int k, s;
  cin >> k >> s;
  int ans = 0;
  for (int i = 0; i <= k; ++i) {
    for (int j = 0; j <= k; ++j) {
      int l = s - i - j;
      if (l >= 0 && l <= k)
        ans++;
    }
  }
  cout << ans << endl;
}