#include <stdio.h>

void printnum(char *);

int main(void)
{
	char before_numbers[191] = "1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991";
	char after_numbers[193] = { '\0' };
	int n, i, j, temp;

	scanf("%d%*c", &n);

	for (i = 0; i < 190;i++) {
		temp = (before_numbers[189 - i] - 48)*n;
		j = 0;
		while (temp != 0) {
			after_numbers[i + j] += temp % 10;
			if (after_numbers[i + j] >= 10) {
				after_numbers[i + j] -= 10;
				after_numbers[i + j + 1]++;
			}
			temp /= 10;
			j++;
		}
	}

	for (i = 0;i < 193;i++) {
		after_numbers[i] += '0';
	}
	i = 0;
	while (after_numbers[192 - i] == '0') {
		after_numbers[192 - i] = '\0';
		i++;
	}

	if (after_numbers[190] == '\0') {
		printf("0");
		printnum(after_numbers);
	}
	else if (after_numbers[191] == '\0') {
		printf("%c", after_numbers[190]);
		printnum(after_numbers);
	}
	else if (after_numbers[192] == '\0') {
		printf("%c%c", after_numbers[191], after_numbers[190]);
		printnum(after_numbers);
	}

	return 0;
}

void printnum(char *after_numbers)
{
	int i;
	printf(".");
	for (i = 0;i < 190;i++) {
		printf("%c", after_numbers[189 - i]);
	}
	printf("\n");
}