#include <cmath>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;

const double INF = 999999999999.9;

int n, a;
long double b;

long double f(long double m, long double M) {
	return (m - M) / (1 + pow(m - a, b));
}

long double gao(long double M) {
	int i, j, k;
	int tc(200);
	long double left, right, mid1, mid2;

	left = a, right = INF;
	while (tc--) {
		mid1 = left + (right - left) / 3;
		mid2 = mid1 + (right - left) / 3;

		if (f(mid1, M) < f(mid2, M)) left = mid1;
		else right = mid2;
	}
	printf("------ %Lf _____ %Lf\n", left,f(left, M) + M);
	return f(left, M) + M;
}

int main() {
	int i, j, k;
	int tc, cn(0);
	long double M, m;

	while (3 == scanf("%d %d %Lf", &n, &a, &b)) {
		M = a;
		for (i=1; i<n; ++i) M = gao(M);
		printf("Case %d: %.2Lf\n", ++cn, M);
	}
	return 0;
}