#include <iostream>
#include <iomanip>

int main() {
    int n;
    std::cin >> n;
    int tens = n / 10;
    int units = n % 10;
    double result = static_cast<double>(tens) / units;
    std::cout << std::fixed << std::setprecision(1) << result << std::endl;
    return 0;
}    
/**************************************************************
	Problem: 1607
	User: fuyijun
	Language: C
	Result: Compile Error
****************************************************************/