#abc258h. [abc258_h]Odd Steps

[abc258_h]Odd Steps

Problem Statement

Find the number, modulo 998244353998244353, of sequences XX that satisfy all of the following conditions.

  • Every term in XX is a positive odd number.
  • The sum of the terms in XX is SS.
  • The prefix sums of XX contain none of A1,dots,ANA_1, \\dots, A_N. Formally, if we define Yi=X1+dots+XiY_i = X_1 + \\dots + X_i for each ii, then YineqAjY_i \\neq A_j holds for all integers ii and jj such that 1leqileqX1 \\leq i \\leq |X| and 1leqjleqN1 \\leq j \\leq N.

Constraints

  • 1leqNleq1051 \\leq N \\leq 10^5
  • $1 \\leq A_1 \\lt A_2 \\lt \\dots \\lt A_N \\lt S \\leq 10^{18}$
  • All values in input are integers.

Input

Input is given from Standard Input in the following format:

NN SS A1A_1 ldots\\ldots ANA_N

Output

Print the answer.


Sample Input 1

3 7
2 4 5

Sample Output 1

3

The following three sequences satisfy the conditions.

  • (1,5,1)(1, 5, 1)
  • (3,3,1)(3, 3, 1)
  • (7)(7)

Sample Input 2

5 60
10 20 30 40 50

Sample Output 2

37634180

Sample Input 3

10 1000000000000000000
1 2 4 8 16 32 64 128 256 512

Sample Output 3

75326268