Problem:
Score : 600 points

Problem Statement

Given are a sequence of N positive integers A_1, A_2, \ldots, A_N and another positive integer S.

For a non-empty subset T of the set \{1, 2, \ldots , N \}, let us define f(T) as follows:

f(T) is the number of different non-empty subsets \{x_1, x_2, \ldots , x_k \} of T such that A_{x_1}+A_{x_2}+\cdots +A_{x_k} = S.

Find the sum of f(T) over all 2^N-1 subsets T of \{1, 2, \ldots , N \}. Since the sum can be enormous, print it modulo 998244353.

Constraints

All values in input are integers.

1 \leq N \leq 3000

1 \leq S \leq 3000

1 \leq A_i \leq 3000

Input

Input is given from Standard Input in the following format:

N S
A_1 A_2 ... A_N

Output

Print the sum of f(T) modulo 998244353.

Sample Input 1

3 4
2 2 4

Sample Output 1

6

For each T, the value of f(T) is shown below. The sum of these values is 6.

f(\{1\}) = 0

f(\{2\}) = 0

f(\{3\}) = 1 (One subset \{3\} satisfies the condition.)

f(\{1, 2\}) = 1 (\{1, 2\})

f(\{2, 3\}) = 1 (\{3\})

f(\{1, 3\}) = 1 (\{3\})

f(\{1, 2, 3\}) = 2 (\{1, 2\}, \{3\})

Sample Input 2

5 8
9 9 9 9 9

Sample Output 2

0

Sample Input 3

10 10
3 1 4 1 5 9 2 6 5 3

Sample Output 3

3296

Solution in PyPy3 (7.3.0) (judge verdict: Wrong Answer)

from collections import defaultdict
n, s = map(int, input().split())
a = list(map(int, input().split()))
MOD = 998244353

bins = [1 for _ in range(n+1)]
for i in range(1, n + 1):
    bins[i] = (2 * bins[i-1]) % MOD

dp = [defaultdict(lambda: 0) for _ in range(s+1)]
dp[0][0] = 1
for v in a:
    if v > s:
        continue
    for i in reversed(range(s-v+1)):
        for length, cnt in dp[i].items():
                dp[i+v][length+1] += cnt

ans = 0

for k, v in dp[s].items():
    ans += (bins[n] // bins[k]) * v
    ans %= MOD

print(ans)