B'XYMXYM and CQXYM will prepare n problems for Codeforces. The difficulty of the problem i will be an integer a_i , where a_i geq 0 . The difficulty of the problems must satisfy a_i+a_{i+1}<m ( 1 <= q i < n ), and a_1+a_n<m , where m is a fixed integer. XYMXYM wants to know how many plans of the difficulty of the problems there are modulo 998 ,244 ,353 . Two plans of difficulty a and b are different only if there is an integer i ( 1 <= q i <= q n ) satisfying a_i neq b_i . A single line contains two integers n and m ( 2 <= q n <= q 50 ,000 , 1 <= q m <= q 10^9 ). Print a single integer -- the number of different plans. In the first test case, the valid a are: [0,0,0] , [0,0,1] , [0,1,0] , [1,0,0] . [1,0,1] is invalid since a_1+a_n geq m . '...