import numba

@numba.jit
def main():
    n, s = list(map(int, input().split()))
    a = list(map(int, input().split()))
    dp = [[None] * (s+1) for _ in range(n+1)]
    M = 998244353


    for j in range(s+1):
        dp[0][j] = 0
    for i in range(n+1):
        dp[i][0] = i+1

    for i in range(1,n+1):
        for j in range(1, s+1):
            dp[i][j] = dp[i-1][j]
            if j-a[i-1]>=0:
                dp[i][j] += dp[i-1][j-a[i-1]]
            dp[i][j] %= M
    total = 0
    for i in range(n+1):
        total += dp[i][s]
    return total%M
if __name__=="__main__":
    print(main())