You are given integers N,M,K,R,C, and V. Find the number of N by M integer matrices a=(a_i,j) that satisfy all of the following conditions, modulo 998244353.
- 1≤a_i,j≤K for all 1≤i≤N,,1≤j≤M.
- a_i,j≤a_i,j+1 for all 1≤i≤N,,1≤j≤M−1.
- a_i,j≤a_i+1,j for all 1≤i≤N−1,,1≤j≤M.
- a_R,C=V.