def count(st): sm=st*(st+1)//2-(st+1)//2 return sm//2 T=int(input()) for _ in range(T): N,K=map(int,input().split()) N-=1 nt=N//pow(10,K) nb=N%pow(10,K) ans=count(nt-1)*count(pow(10,K)-1) ls=nt//2 ls*=count(pow(10,K)-1)-count(pow(10,K)-2-nb) print((ans+ls)%998244353)