#include<stdio.h>
int main()
{
	int a;
	scanf("%d",&a);
	printf("%.1f",(a/10)*1.0/(a%10));
	return 0;
}
/**************************************************************
	Problem: 1607
	User: admin
	Language: C
	Result: Accepted
	Time:11 ms
	Memory:1144 kb
****************************************************************/