C++ :

#include <bits/stdc++.h>
using namespace std ;
int x, n ;
double f(int x, int n) {
    if(n == 1) return (double) x / (1 + x) ;
    return (double)x / (n + f(x, n - 1)) ;
}
int main() {
    cin >> x >> n ;
    printf("%.2lf", f(x, n)) ;
    return 0 ;
}