#include <iostream>


using namespace std;


int main()
{
    int a,b;
    int suma =0;
    cin>>a>>b;
    if(b == 1) {
        cout << a / 100 << endl;
    }
    else if(b == 2) {
        cout << (a / 10) % 10 << endl;
    }
    else if(b == 3) {
        cout <<a % 10 << endl;
    }
    else {
        
        
        for(int i =1;i<=b-3;i++){
            int posledna_cifra = a%10;
            int vtora_cifra = (a/10)%10;
            int prva_cifra = a/100;
            suma=posledna_cifra+vtora_cifra+prva_cifra;
            int c=suma%10;
            a*=10;
            a+=c;
            a%=1000;
            
            
        }
        cout<<a%10<<endl;
    }
    return 0;
}