#include <fstream>
using namespace std;
ifstream fin("control1.in");
ofstream fout("control1.out");
int a,b,c,s,i,cs;int z, k;
int main()
{
    fin>>a>>b>>c;
    for(i=a;i<=b;i++)
    {
        s=0;
        z=i;
        while(z)
            {
                s=s+z%10;
                z=z/10;

            }
                if(s>=10)
                    {
                        cs=0;
                        while(s)
                        {
                            cs=cs+s%10;
                            s=s/10;
                        }
                        if(cs==c)
                                k++;
                    }
                else if(s==c)
                    k++;
    }
    fout<<k;
    return 0;
}