// yukicoder: No.746 7の倍数
// 2019.4.21 bal4u

#include <stdio.h>

#if 1
#define gc() getchar_unlocked()
#define pc(c) putchar_unlocked(c)
#else
#define gc() getchar()
#define pc(c) putchar(c)
#endif
int in()    // 非負整数の入力
{
	int n = 0, c = gc();
	do n = 10 * n + (c & 0xf), c = gc(); while (c >= '0');
	return n;
}

void outs(char *s) { while (*s) pc(*s++); }

char s[] = "142857", *p = s;

int main()
{
	int N, k;

	N = in();
	pc('0');
	if (N > 0) {
		pc('.');
		k = N/6; while (k--) outs(s);
		k = N%6; while (k--) pc(*p++);
	}
	pc('\n');
	return 0;
}