#include<bits/stdc++.h>
#define poly vector<int>
#define IOS ios::sync_with_stdio(false)
#define ll long long
#define mp make_pair
#define mt make_tuple
#define pa pair < int,int >
#define fi first
#define se second
#define inf 1e18
#define mod 998244353
#define sz(x) ((int)((x).size()))
#define int ll
// #define N 
using namespace std;
string L,R;
int l,r;
int n;
int C[3005][3005];
inline ll quickPower(ll x,ll y)
{
	ll res=1;
	while (y)
	{
		if (y&1) res=res*x%mod;
		x=x*x%mod;
		y>>=1;
	}
	return res;
}
inline int md(string x)
{
	int res=0;
	for (auto u:x) res=(res*10+u-'0')%mod;
	return res;
}
inline int Cc(int x,int y)
{
	int res=1;
	for (int i=1;i<=y;i++) res=res*i%mod;
	res=quickPower(res,mod-2);
	for (int i=x;i>x-y;i--)
		res=res*i%mod;
	return res;
}
inline int F(int x,int i)
{
	int res=0;
	{
		int coef=1;
		if (i&1) coef=mod-1;
		coef=coef*C[n][i]%mod;
		coef=coef*Cc((x-l*(n-i)%mod-(r+1)*i%mod+n-1+mod+mod)%mod,n-1)%mod;
		res=(res+coef)%mod;
	}
	return res;
}
inline poly mul(poly &x,poly &y)
{
	poly res(x.size()+y.size()-1,0);
	for (int i=0;i<x.size();i++)
		for (int j=0;j<y.size();j++)
			res[i+j]=(res[i+j]+x[i]*y[j]%mod)%mod;
	return res;
}
inline poly add(poly &x,poly &y)
{
	poly res(max(x.size(),y.size()),0);
	for (int i=0;i<res.size();i++)
	{
		if (i<x.size()) res[i]=(res[i]+x[i])%mod;
		if (i<y.size()) res[i]=(res[i]+y[i])%mod;
	}
	return res;
}
inline poly div(poly &x,poly &y)
{
	poly nw=x;
	poly res(x.size()+1-y.size(),0);
	for (int i=x.size()-y.size();i>=0;i--)
	{
		res[i]=nw[i+y.size()-1]*quickPower(y.back(),mod-2)%mod;
		for (int j=y.size()-1;j>=0;j--)
		{
			nw[i+j]=(nw[i+j]-res[i]*y[j]%mod+mod)%mod;
		}
	}
	return res;
}	
inline poly cz(poly &a,poly &b)
{
	poly res(1,0);
	poly nw(1,1);
	for (int i=0;i<a.size();i++)
	{
		poly now(2,0);
		now[1]=1,now[0]=(mod-a[i])%mod;
		nw=mul(nw,now);
	}
	for (int i=0;i<a.size();i++)
	{
		poly now(2,0);
		now[1]=1,now[0]=(mod-a[i])%mod;
		nw=div(nw,now);
		int o=1;
		for (int j=0;j<a.size();j++)
			if (j!=i)
			{
				o=o*(a[i]-a[j]+mod)%mod;
			}
		o=quickPower(o,mod-2);
		o=o*b[i]%mod;
		if (o)
		{
			for (auto &u:nw) u=u*o%mod;
			res=add(res,nw);
			o=quickPower(o,mod-2);
			for (auto &u:nw) u=u*o%mod;
		}
		nw=mul(nw,now);
	}
	while (res.size()&&res.back()==0) res.pop_back();
	return res;
}
int vis[3005][11][2],DFN;
poly dp[3005][11][2];
poly all;
poly bL,bR;
int pw[3005];
inline poly dfs(int x,int lst,int y)
{
	if (x==-1)
	{
		poly g(n+1,0);
		g[0]=1;
		return g;
	}
	if (vis[x][lst][y]==DFN||!y&&vis[x][lst][y]) return dp[x][lst][y];
	vis[x][lst][y]=DFN;
	poly res(n+1,0);
	for (int i=min(9ll,lst);i>=0;i--)
	{
		if (y&&i>all[x]) continue;
		poly g=dfs(x-1,((lst!=10||lst==10&&i)?i:lst),y&(i==all[x]));
		for (int j=0;j<=n;j++)
			for (int k=0,c=1;j+k<=n;k++,c=c*pw[x]%mod*i%mod)
				res[j+k]=(res[j+k]+g[j]*c%mod*C[j+k][j]%mod)%mod;
	}
	dp[x][lst][y]=res;
	return res;
}
inline poly calc(poly &x)
{
	++DFN;
	all=x;
	pw[0]=1;
	for (int i=1;i<=sz(all);i++) pw[i]=pw[i-1]*10%mod;
	return dfs(sz(all)-1,10,1);
}
inline poly mul(poly g,int n)
{
	poly res(g.size()+10,0);
	int x=0;
	for (int i=0;i<res.size();i++)
	{
		if (i<sz(g))
			x+=g[i]*n;
		res[i]=x%10,x/=10;
	}
	while (res.size()>1&&res.back()==0) res.pop_back();
	return res;
}
inline poly add1(poly x,poly y)
{
	poly res(max(x.size(),y.size())+5,0);
	for (int i=0;i+1<res.size();i++)
	{
		if (i<sz(x)) res[i]=(res[i]+x[i]);
		if (i<sz(y)) res[i]=(res[i]+y[i]);
		res[i+1]+=res[i]/10;
		res[i]%=10;
	}
	while (res.size()>1&&res.back()==0) res.pop_back();
	return res;
}
void BellaKira()
{
	cin>>L>>R;
	for (auto u:R) bR.push_back(u-'0');
	reverse(bR.begin(),bR.end());
	for (auto u:L) bL.push_back(u-'0');
	reverse(bL.begin(),bL.end());
	cin>>n;
	C[0][0]=1;
	for (int i=1;i<=n;i++)
	{
		C[i][0]=1;
		for (int j=1;j<=i;j++) C[i][j]=(C[i-1][j-1]+C[i-1][j])%mod;
	}
	l=md(L);
	r=md(R);
	int ans=0;
	bR.push_back(0);
	for (int i=0;i<sz(bR);i++)
		if (bR[i]!=9)
		{
			bR[i]++;
			for (int j=0;j<i;j++) bR[j]=0;
			break;
		}
	poly Lim=mul(bR,n);
	poly g=calc(Lim);
	for (int i=0;i<=n;i++)
	{
		poly bd=add1(mul(bL,(n-i)),mul(bR,i));
		for (int j=0;j<bd.size();j++)
			if (bd[j])
			{
				bd[j]--;
				for (int k=0;k<j;k++) bd[k]=9;
				break;
			}
		poly gg=calc(bd);
		// cerr<<i<<endl;
		for (int j=0;j<=n;j++) g[j]=(g[j]-gg[j]+mod)%mod;
		poly gx,gy;
		for (int j=12311;;j++)
		{
			if (gx.size()==100) break;
			gx.push_back(j);
			gy.push_back(F(j,i));
		}
		poly coef=cz(gx,gy);
		for (int j=0;j<sz(coef)&&j<=n;j++)
			ans=(ans+coef[j]*g[j]%mod)%mod;
		for (int j=0;j<=n;j++) g[j]=(g[j]+gg[j])%mod;
	}

	cout<<ans<<'\n';
}
signed main()
{
	// freopen("1.in","r",stdin);
	IOS;
	cin.tie(0);
	int T=1;
	while (T--)
	{
		BellaKira();
	}
}
/*list:
1.mod 998244353 or 1e9+7 or ???
2.N
3.duipai shuju xingtai duoyidian
...
*/