---

#include <math.h>
#include <stdio.h>

int main(void) {
	double x;

	if (scanf("%lf", &x) != 1 || !isfinite(x) || x == 0) {
		printf("n/a");
	} else {
		int c = getchar();

		while (c == ' ' || c == '\t' || c == '\r') {
			c = getchar();
		}

		if (c == '\n' || c == EOF) {
			double y = 7e-3 * pow(x, 4)
				+ ((22.8 * cbrt(x) - 1e3) * x + 3) / (x * x / 2)
				- x * pow(10 + x, 2 / x) - 1.01;

			if (isfinite(y)) {
				printf("%.1f", y);
			} else {
				printf("n/a");
			}
		} else {
			printf("n/a");
		}
	}

	return 0;
}