1073E

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#define rep(i,l,r) for (int i=(l); i<=(r); i++)
typedef long long ll;
using namespace std;

int k,a[20],pw[20],mod=998244353;
struct P{ int x,y; }f[20][1050][2];
ll l,r;

P dfs(int x,int S,bool lim,bool b){
	if (!x) return (P){1,0};
	if (!lim && ~f[x][S][b].y) return f[x][S][b];
	P ans=(P){0,0};
	int ed=lim?a[x]:9;
	rep(i,0,ed){
		int S2=S|((b||i)<<i);
		if (__builtin_popcount(S2)>k) continue;
		P tmp=dfs(x-1,S2,lim&(i==ed),b||i);
		ans.x=(ans.x+tmp.x)%mod; ans.y=(ans.y+tmp.y+1ll*i*pw[x-1]%mod*tmp.x%mod)%mod;
	}
	if (!lim) f[x][S][b]=ans;
	return ans;
}

int calc(ll n){
	int tot=0;
	while (n) a[++tot]=n%10,n/=10;
	memset(f,-1,sizeof(f));
	return dfs(tot,0,1,0).y;
}

int main(){
	pw[0]=1; rep(i,1,20) pw[i]=1ll*pw[i-1]*10%mod;
	cin>>l>>r>>k; cout<<((calc(r)-calc(l-1))%mod+mod)%mod;
	return 0;
}