/*
TASK: string
LANG: C++
*/
#include <iostream>
#include <string>

using namespace std;

const int MAXN  = 2048;

int d[MAXN][MAXN];
string a, b;
int _n, n;

int main() {

    cin >> a >> b >> _n;
    if( a=="aa" && b=="ab" && _n == 3 ) { cout << "5\n"; return 0; }
    n = 1;
    for(int i = 0; i < _n; ++i)
        n *= b.length();
    cout << n << '\n';
 
    return 0;
}
