#include <iostream>
#include <cmath>
using namespace std;
//[[Rcpp::export]]
int jiecheng(int n){
int temp=1;
if(n==1)
return 1;
else
for(int i=1;i<=n;i++){
temp*=i;
}
return temp;
}
//[[Rcpp::export]]
double NMLP(double t){
const double pi=3.141593;
double sum=1.0,jsx=0.0;
int n=1;
while(n<45){
jsx=pow(-1,n)*pow(t,2*n)/(jiecheng(n)*pow(2,n)*(2*n+1));
sum+=jsx;
n+=1;
}
double Ft=0.5+t/sqrt(2*pi)*sum;
return Ft;
}
int main(){
double x;
cout<<"please input the number:";
cin>>x;
cout<<NMLP(x)<<endl;
return 0;
}