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

/*input
10 10
3 1 4 1 5 9 2 6 5 3
*/
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

#define int long long
#define double long double
#define f first
#define s second
#define mp make_pair
#define pb push_back

#define RE(i, n) for (int i = 1; i <= n; i++)
#define RED(i, n) for (int i = n; i > 0; i--)
#define REPS(i, n) for (int i = 1; (i * i) <= n; i++)
#define REP(i, n) for (int i = 0; i < (int)n; i++)
#define FOR(i, a, b) for (int i = a; i < b; i++)
#define REPD(i, n) for (int i = n - 1; i >= 0; i--)
#define FORD(i, a, b) for (int i = a; i >= b; i--)

#define all(v) v.begin(), v.end()
#define pii pair<int, int>
#define vi vector<int>
#define vvi vector<vi>
#define print(arr)                                                             \\
  for (auto it = arr.begin(); it != arr.end(); ++it)                           \\
    cout << *it << " ";                                                        \\
  cout << endl;
#define debug(x) cout << x << endl;
#define debug2(x, y) cout << x << " " << y << endl;
#define debug3(x, y, z) cout << x << " " << y << " " << z << endl;

typedef tree<int, null_type, less<int>, rb_tree_tag,
             tree_order_statistics_node_update>
    ordered_set;

const int INF = 1e18 + 1;
const int MOD = 998244353;
const double PI = 3.14159265358979323846264338;

int raise(int a, int n, int m = MOD) {
  if (n == 0)
    return 1;
  if (n == 1)
    return a;
  int x = 1;
  x *= raise(a, n / 2, m);
  x %= m;
  x *= x;
  x %= m;
  if (n % 2)
    x *= a;
  x %= m;
  return x;
}

int floor1(int n, int k) {
  if (n % k == 0 || n >= 0)
    return n / k;
  return (n / k) - 1;
}

int ceil1(int n, int k) { return floor1(n + k - 1, k); }

const int N = 3001;
int dp[N][N];
int n, s;
int a[N];

void solve() {
  cin >> n >> s;
  RE(i, n) { cin >> a[i]; }
  dp[0][0] = raise(2, n, MOD);
  int inv2 = raise(2, MOD - 2, MOD);
  RE(i, n) {
    REP(j, s + 1) {
      dp[i][j] = dp[i - 1][j];
      if (a[i] <= j) {
        int what = dp[i - 1][j - a[i]];
        what *= inv2;
        what %= MOD;
        dp[i][j] += what;
        dp[i][j] %= MOD;
      }
    }
  }
  cout << dp[n][s];
}

signed main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  // freopen(".in","r",stdin);freopen(".out","w",stdout);
  int t = 1;
  // cin >> t;
  while (t--) {
    solve();
  }
  return 0;
}

Error: TLE

Fixed submission:

/*input
10 10
3 1 4 1 5 9 2 6 5 3
*/
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

#define int long long
#define double long double
#define f first
#define s second
#define mp make_pair
#define pb push_back

#define RE(i, n) for (int i = 1; i <= n; i++)
#define RED(i, n) for (int i = n; i > 0; i--)
#define REPS(i, n) for (int i = 1; (i * i) <= n; i++)
#define REP(i, n) for (int i = 0; i < (int)n; i++)
#define FOR(i, a, b) for (int i = a; i < b; i++)
#define REPD(i, n) for (int i = n - 1; i >= 0; i--)
#define FORD(i, a, b) for (int i = a; i >= b; i--)

#define all(v) v.begin(), v.end()
#define pii pair<int, int>
#define vi vector<int>
#define vvi vector<vi>
#define print(arr)                                                             \\
  for (auto it = arr.begin(); it != arr.end(); ++it)                           \\
    cout << *it << " ";                                                        \\
  cout << endl;
#define debug(x) cout << x << endl;
#define debug2(x, y) cout << x << " " << y << endl;
#define debug3(x, y, z) cout << x << " " << y << " " << z << endl;

typedef tree<int, null_type, less<int>, rb_tree_tag,
             tree_order_statistics_node_update>
    ordered_set;

const int INF = 1e18 + 1;
const int MOD = 998244353;
const double PI = 3.14159265358979323846264338;

int raise(int a, int n, int m = MOD) {
  if (n == 0)
    return 1;
  if (n == 1)
    return a;
  int x = 1;
  x *= raise(a, n / 2, m);
  x %= m;
  x *= x;
  x %= m;
  if (n % 2)
    x *= a;
  x %= m;
  return x;
}

int floor1(int n, int k) {
  if (n % k == 0 || n >= 0)
    return n / k;
  return (n / k) - 1;
}

int ceil1(int n, int k) { return floor1(n + k - 1, k); }

const int N = 3001;
int dp[N][N];
int n, s;
int a[N];

void solve() {
  cin >> n >> s;
  RE(i, n) { cin >> a[i]; }
  dp[0][0] = raise(2, n, MOD);
  RE(i, n) {
    REP(j, s + 1) {
      dp[i][j] = dp[i - 1][j];
      if (a[i] <= j) {
        int what = dp[i - 1][j - a[i]];
        what *= raise(2, MOD - 2, MOD);
        what %= MOD;
        dp[i][j] += what;
        dp[i][j] %= MOD;
      }
    }
  }
  cout << dp[n][s];
}

signed main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  // freopen(".in","r",stdin);freopen(".out","w",stdout);
  int t = 1;
  // cin >> t;
  while (t--) {
    solve();
  }
  return 0;
}