#include <iostream>
#include <cmath>
using namespace std;

int factorial(int n) {
      int result = 1;
 
      for ( int i = 2; i <= n; i++ ) {
          result *= i;
      }
      return result;
}

float sh(float x, float result, int n) {
    if( n == 0 ) {
        return result;
    }
    result += pow(x, 2*n-1)/factorial(2*n-1);
    sh(x, result, n - 1);
}

int main() {
    int n;
    float x, result;
    
    cout << "write x = "; cin >> x; cout << endl;
    cout << "write n = "; cin >> n; cout << endl;
    
    result = sh(x, 0, n);
    cout << "sh(" << x << ") = " << result << endl;
    
    return 0;
}