#include <iostream>
#include <iomanip>
#include <algorithm>
#include <vector>
#include <stack>
#include <queue>
#include <string>
#include <math.h>
using namespace std;

void main()
{
    int k,l,m;
    cin >> k >> l >> m;

    if (k>l || m<0 || k<=1 || l<=1)
    {
        cout << "WTF?";
        return;
    }

    queue<int> q;
    if (m==0) q.push(0);

    while(m!=0)
    {
        q.push(m%l);
        m/=l;
    }

    int n=0;
    int b=1;
    while(q.empty()==false)
    {
        int d=q.front();
        if (d>=k)
        {
            cout << "WTF?";
            return;
        }
        n+=b*d;
        b*=k;

        q.pop();
    }

    cout << n;
}