### BUGGY CODE ###

# -*- coding: utf-8 -*-
import bisect
import heapq
import math
import random
import sys
from collections import Counter, defaultdict, deque
from decimal import ROUND_CEILING, ROUND_HALF_UP, Decimal
from functools import lru_cache, reduce
from itertools import combinations, combinations_with_replacement, product, permutations
from operator import add, mul, sub

sys.setrecursionlimit(100000)
input = sys.stdin.readline
INF = 2**62-1

def read_int():
    return int(input())


def read_int_n():
    return list(map(int, input().split()))


def read_float():
    return float(input())


def read_float_n():
    return list(map(float, input().split()))


def read_str():
    return input().strip()


def read_str_n():
    return list(map(str, input().split()))


def error_print(*args):
    print(*args, file=sys.stderr)


def mt(f):
    import time

    def wrap(*args, **kwargs):
        s = time.time()
        ret = f(*args, **kwargs)
        e = time.time()

        error_print(e - s, 'sec')
        return ret

    return wrap


class Mod:
    def __init__(self, m):
        self.m = m

    def add(self, a, b):
        return (a + b) % self.m

    def sub(self, a, b):
        return (a - b) % self.m

    def mul(self, a, b):
        return ((a % self.m) * (b % self.m)) % self.m

    def div(self, a, b):
        return self.mul(a, pow(b, self.m-2, self.m))

    def pow(self, a, b):
        return pow(a, b, self.m)



@mt
def slv(N, S, A):
    M = 998244353
    ans = 0

    @lru_cache(maxsize=None)
    def f(i, n):
        if n == 0:
            return N - i + 1
        elif n < 0:
            return 0
        elif i == N:
            return 0 if n != 0 else 1
        return (f(i+1, n-A[i]) + f(i+1, n)) % M

    for i in range(N):
        ans += f(i, S)
        ans %= M

    return ans


def main():
    N, S = read_int_n()
    A = read_int_n()
    print(slv(N, S, A))

    # N = 3000
    # S = random.randint(1, 3000)
    # A = [random.randint(1, 3000) for _ in range(N)]
    # print(slv(N, S, A))



if __name__ == '__main__':
    main()


### FIXED CODE ###

# -*- coding: utf-8 -*-
import bisect
import heapq
import math
import random
import sys
from collections import Counter, defaultdict, deque
from decimal import ROUND_CEILING, ROUND_HALF_UP, Decimal
from functools import lru_cache, reduce
from itertools import combinations, combinations_with_replacement, product, permutations
from operator import add, mul, sub

sys.setrecursionlimit(100000)
input = sys.stdin.readline
INF = 2**62-1


def read_int():
    return int(input())


def read_int_n():
    return list(map(int, input().split()))


def read_float():
    return float(input())


def read_float_n():
    return list(map(float, input().split()))


def read_str():
    return input().strip()


def read_str_n():
    return list(map(str, input().split()))


def error_print(*args):
    print(*args, file=sys.stderr)


def mt(f):
    import time

    def wrap(*args, **kwargs):
        s = time.time()
        ret = f(*args, **kwargs)
        e = time.time()

        error_print(e - s, 'sec')
        return ret

    return wrap


class Mod:
    def __init__(self, m):
        self.m = m

    def add(self, a, b):
        return (a + b) % self.m

    def sub(self, a, b):
        return (a - b) % self.m

    def mul(self, a, b):
        return ((a % self.m) * (b % self.m)) % self.m

    def div(self, a, b):
        return self.mul(a, pow(b, self.m-2, self.m))

    def pow(self, a, b):
        return pow(a, b, self.m)


@mt
def slv(N, S, A):
    M = 998244353
    ans = 0

    dp = [0] * (S+1)
    for a in A:
        dp[0] += 1
        ndp = [0] * (S+1)
        for j in range(S+1):
            ndp[j] += dp[j]
            ndp[j] %= M
            if j+a <= S:
                ndp[j+a] += dp[j]
                ndp[j+a] %= M
        dp = ndp
        ans += dp[S]
        ans %= M

    return ans


def main():
    N, S = read_int_n()
    A = read_int_n()
    print(slv(N, S, A))


if __name__ == '__main__':
    main()