#include <cstdio>#include <algorithm>#include <cstring> using namespace std;typedef long long ll;const int N=25,M=10005;int bit[N],pw[5],k;ll dp[N][M][2][2],l,r;ll DP(int d,int x,bool f,bool lim){    int c[5];    if(d==-1)return 1;    ll &ret=dp[d][x][f][lim];    if(~ret)return ret; ret=0;    int st=k-1,y=x,pos=0;    for(int i=0;i<k;i++)c[i]=y%10,y/=10;    if(!f){while(!c[st]&&st>=0)st--;}    for(int i=st;i>=0;i--)pos|=1<<c[i];    int up=lim?bit[d]:9;    for(int i=0;i<=up;i++){        if(pos>>i&1)continue;        if(f)ret+=DP(d-1,(x-pw[k-1]*c[k-1])*10+i,f,lim&&i==up);        else if(st==-1&&!i)ret+=DP(d-1,0,0,lim&&i==up);        else ret+=DP(d-1,x*10+i,st==k-2,lim&&i==up);    }return ret;}ll Cal(ll x){    if(!x)return 1;int cnt=0;    while(x)bit[cnt++]=x%10,x/=10;    memset(dp,-1,sizeof(dp));    return DP(cnt-1,0,0,1);}int main(){    for(int i=pw[0]=1;i<5;i++)pw[i]=pw[i-1]*10;    while(~scanf("%lld%lld%d",&l,&r,&k)){        k--;printf("%lld\n",Cal(r)-Cal(l-1));    }return 0;}