#include #define all(v) v.begin(), v.end() #define rep(i, n) for (int i = 0; i < (int)(n); i++) #define con_input(v) for(auto it=v.begin();it!=v.end();it++){cin>>*it;} #define con_debug(v) for(auto it=v.begin();it!=v.end();it++){cerr<<*it<<" ";}cerr<T digitsum(T n); template bool isPrime(T n); template vector> prime_factor(T n); long long int intpow(long long int,long long int); template T intlog(T); long long int combination(long long int,long long int); int main(){ int n; cin>>n; printf("%.8lf\n",(double)1/n); }