#define MD 998244353
ll@(N,M,K,L);Comb<mint>c;wt(sum[v,L,M](sum[i,0,N]((-1)**i*c.C(N-1,i)*(c.C(N-2+M*K-v-M*i-i,N-2)-c.C(N-2+M*K-v-v*i-i,N-2)))));