Problem p02662 (C++) — buggy submission, verdict: Time Limit Exceeded

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<vector<vector<ll>>> vvvll;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
typedef vector<vector<vector<bool>>> vvvb;
typedef pair<ll, ll> pll;
typedef vector<pll> vpll;
typedef vector<vpll> vvpll;
typedef vector<double> vd;
typedef vector<vd> vdd;

#define FOR(i, x, y) for (ll i = (ll)x; i < (ll)y; ++i)
#define REP(i, y) FOR(i, 0, y)
#define RFOR(i, x, y) for (ll i = (ll)x; i >= (ll)y; --i)
#define RREP(i, x) RFOR(i, x, 0)
#define ALL(a) a.begin(), a.end()
#define pb push_back
#define debug_print(x...)                                                      \\
  cerr << "line " << __LINE__ << " : ";                                        \\
  debug_print_in(x);

template <typename First> void debug_print_in(First first) {
  cerr << first << endl;
  return;
}

template <typename First, typename... Rest>
void debug_print_in(First first, Rest... rest) {
  cerr << first << " ";
  debug_print_in(rest...);
  return;
}

void IN(void) { return; }

template <typename First, typename... Rest>
void IN(First &first, Rest &...rest) {
  cin >> first;
  IN(rest...);
  return;
}

template <typename First> void OUT(First first) {
  cout << first << endl;
  return;
}

template <typename First, typename... Rest>
void OUT(First first, Rest... rest) {
  cout << first << " ";
  OUT(rest...);
  return;
}

template <class t, class u> void chmax(t &a, u b) {
  if (a < b)
    a = b;
};
template <class t, class u> void chmin(t &a, u b) {
  if (a > b)
    a = b;
};
int popcount(int t) { return __builtin_popcount(t); }  // GCC
int popcount(ll t) { return __builtin_popcountll(t); } // GCC

template <typename T> void vec_print(vector<T> VEC) {
  REP(i, VEC.size()) { cerr << VEC[i] << " "; }
  cerr << endl;
};

template <typename T>
void mat_print(vector<vector<T>> MAT){
    REP(i, MAT.size()){REP(j, MAT[i].size()){cerr << MAT[i][j] << " ";
}
cerr << endl;
}
}
;

constexpr int INF = (1 << 30);
constexpr ll INFLL = 1LL << 62;
constexpr long double EPS = 1e-12;
constexpr ll MOD = (ll)(998244353);

ll N, S;
vll A;
vector<vector<ll>> dp;

void search(ll index) {
  if (index >= N)
    return;
  // debug_print(A[index]);
  // debug_print("\\n");
  dp[1] = dp[0];
  REP(i, S + 1 - A[index]) {
    /*
    auto mp_prev = dp[0][i];
    for(auto itr : mp_prev){
      dp[1][i+A[index]][itr.first+1] += itr.second;
    }
    */
    dp[1][i + A[index]] += dp[0][i] * (MOD / 2 + 1) % MOD;
    dp[1][i + A[index]] %= MOD;
  }
  dp[0] = dp[1];

  /*
  REP(i,S+1){
    for(auto itr : dp[0][i]){
      debug_print(i, itr.first, itr.second);
    }
  }
  debug_print("\\n");
  */

  search(index + 1);
  return;
}

int main() {
  cin.tie(0); // cut the cin and cout (default, std::flush is performed after
              // std::cin)
  ios::sync_with_stdio(
      false); // cut the iostream and stdio (DON'T endl; BUT "\\n";)

  IN(N, S);
  A.resize(N);
  REP(i, N) IN(A[i]);

  dp.resize(2);
  REP(i, 2) { dp[i].resize(S + 1); }

  vll pow2(N + 1, 1);
  REP(i, N) { pow2[i + 1] = (pow2[i] * 2) % MOD; }

  dp[0][0] = pow2[N];

  search(0);

  OUT(dp[1][S]);

  /*
  auto mp = dp[1][S];

  ll ans = 0;
  for(auto itr : mp){
    //debug_print(itr.first, itr.second);
    ans += (itr.second * pow2[N-itr.first])%MOD;
    ans %= MOD;
  }

  OUT(ans);
  */

  return 0;
}


Error: TLE

Fixed submission:

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<vector<vector<ll>>> vvvll;
typedef vector<bool> vb;
typedef vector<vector<bool>> vvb;
typedef vector<vector<vector<bool>>> vvvb;
typedef pair<ll, ll> pll;
typedef vector<pll> vpll;
typedef vector<vpll> vvpll;
typedef vector<double> vd;
typedef vector<vd> vdd;

#define FOR(i, x, y) for (ll i = (ll)x; i < (ll)y; ++i)
#define REP(i, y) FOR(i, 0, y)
#define RFOR(i, x, y) for (ll i = (ll)x; i >= (ll)y; --i)
#define RREP(i, x) RFOR(i, x, 0)
#define ALL(a) a.begin(), a.end()
#define pb push_back
#define debug_print(x...)                                                      \\
  cerr << "line " << __LINE__ << " : ";                                        \\
  debug_print_in(x);

template <typename First> void debug_print_in(First first) {
  cerr << first << endl;
  return;
}

template <typename First, typename... Rest>
void debug_print_in(First first, Rest... rest) {
  cerr << first << " ";
  debug_print_in(rest...);
  return;
}

void IN(void) { return; }

template <typename First, typename... Rest>
void IN(First &first, Rest &...rest) {
  cin >> first;
  IN(rest...);
  return;
}

template <typename First> void OUT(First first) {
  cout << first << endl;
  return;
}

template <typename First, typename... Rest>
void OUT(First first, Rest... rest) {
  cout << first << " ";
  OUT(rest...);
  return;
}

template <class t, class u> void chmax(t &a, u b) {
  if (a < b)
    a = b;
};
template <class t, class u> void chmin(t &a, u b) {
  if (a > b)
    a = b;
};
int popcount(int t) { return __builtin_popcount(t); }  // GCC
int popcount(ll t) { return __builtin_popcountll(t); } // GCC

template <typename T> void vec_print(vector<T> VEC) {
  REP(i, VEC.size()) { cerr << VEC[i] << " "; }
  cerr << endl;
};

template <typename T>
void mat_print(vector<vector<T>> MAT){
    REP(i, MAT.size()){REP(j, MAT[i].size()){cerr << MAT[i][j] << " ";
}
cerr << endl;
}
}
;

constexpr int INF = (1 << 30);
constexpr ll INFLL = 1LL << 62;
constexpr long double EPS = 1e-12;
constexpr ll MOD = (ll)(998244353);

ll N, S;
vll A;
vector<vector<unordered_map<ll, ll>>> dp;

void search(ll index) {
  if (index >= N)
    return;
  // debug_print(A[index]);
  // debug_print("\\n");
  dp[1] = dp[0];
  REP(i, S + 1 - A[index]) {
    auto mp_prev = dp[0][i];
    for (auto itr : mp_prev) {
      dp[1][i + A[index]][itr.first + 1] += itr.second;
    }
  }
  dp[0] = dp[1];

  /*
  REP(i,S+1){
    for(auto itr : dp[0][i]){
      debug_print(i, itr.first, itr.second);
    }
  }
  debug_print("\\n");
  */

  search(index + 1);
  return;
}

int main() {
  cin.tie(0); // cut the cin and cout (default, std::flush is performed after
              // std::cin)
  ios::sync_with_stdio(
      false); // cut the iostream and stdio (DON'T endl; BUT "\\n";)

  IN(N, S);
  A.resize(N);
  REP(i, N) IN(A[i]);

  dp.resize(2);
  REP(i, 2) { dp[i].resize(S + 1); }

  dp[0][0][0] = 1;

  search(0);

  vll pow2(N + 1, 1);
  REP(i, N) { pow2[i + 1] = (pow2[i] * 2) % MOD; }

  auto mp = dp[1][S];

  ll ans = 0;
  for (auto itr : mp) {
    // debug_print(itr.first, itr.second);
    ans += (itr.second * pow2[N - itr.first]) % MOD;
    ans %= MOD;
  }

  OUT(ans);

  return 0;
}