Untitled

#include <cmath>
#include <cstdio>
#include <cstdlib>

using namespace std;

int main()
{
    int x, desired_error, exp_approx, i, factorial = 1, number;
   cout << "calculate exp(x) with the Taylor series approximation ";
   cout << "\nexp_approx = 1 + x + x^2 / 2! + x^3 / 3! + x^i/i!\n";
   
    cout << " input x, i and a desired number of series\n ";
  
  cin >> x;
  cin >> number;
  cin >> desired_error;
  
for(i= number; i<=number; i++){
     if(abs( exp_approx - exp(x) ) < desired_error) {
     
        break;
        
    }
    else if(number < 0){
        cout << "Error ! factorial of a negative number doesn't exist";
        break;
    }

     else{
         
          factorial *= i;
         
     }
    
        exp_approx = 1 + x + pow(x,2)/2*factorial + pow(x,3)/3*factorial + pow(x,i)/i*factorial;
      
}
    cout <<  "exp_approx =" << exp_approx;  
    
    

  
  
  
  
    return 0;
}