#include <iostream>
#include <iomanip>
#include <math.h>
using namespace std;

int main()
{
    int T = 0, l, h, k;
    cin >> l >> h >> k;
    while (l >= 0)
    {
        ++T;
        double S = 0;
        int e;
        for (int i = l; i <= h; ++i)
        {
            e = floor(k*log10((double)h));
            S += pow(10, k*log10((double)i)-e);
        }
        while (S >= 1) {S /= 10; ++e;}
        cout << "Case ";
        cout << setfill('0') << setw(4) << T << ": ";
        if (S)
        {
            cout << fixed << setprecision(6) << S << 'e';
            cout << setfill('0') << setw(10) << e << endl;
        }
        else cout << "0.000000e0000000001" << endl;
        cin >> l >> h >> k;
    }
    return 0;
}