Programmieren lernen

n = int(raw_input("N: "))
i =1
fact =1
while (i<=n):
    fact = fact*i
    i = i+1
print'fact('+str(n)+') = '+str(fact)
                

package ch.programmieraufgaben.iteration;

import java.util.Scanner;


public class Fakultaet {
  public static void main(String[] args) {
    new Fakultaet().top();
  }
  
  void top() {
     int  n         = einlesenInt ("n");
     long fact      = 1;
     
     while(n > 0) {
         fact = n * fact;
         n    = n - 1;
     }
     
     System.out.println("Fakultaet = " + fact);  
  }
  
  // generelle Hilfsfunktionen
  Scanner sc = new Scanner(System.in);
  int einlesenInt(String wert) {
      meldung(wert);
      return sc.nextInt();
  }
  
  void meldung(String wert) {
    System.out.println("Bitte " + wert + " eingeben:" );
  }
  
} // end of class Fakultaet
                

Lösung von: Philipp G. Freimann (BBW (Berufsbildungsschule Winterthur) https://www.bbw.ch)

# Fakultät
def fak(n):
    summe = 1
    i = 1
    while i < n+1:
        summe = summe * i
        i = i + 1
    return summe

# n!
print( fak(20) )
                

Lösung von: Alex Groeg (Freies Lernen)

Math.factorial = function(num) {
  let res = 1, i;
  for (i = 1; i <= num; i++) res *= i;
  return res;
}

// ausgaben
console.log(Math.factorial(10));      // 3628800
console.log(Math.factorial(100));     // 9.33262154439441e+157
console.log(Math.factorial(1000));    // Infinity ;)

                                      // lissalanda@gmx.at
                

Lösung von: Lisa Salander (Heidi-Klum-Gymnasium Bottrop)

using System.Numerics;

// 1. iterativ 
static BigInteger FacIter(int n) {
    BigInteger result = 1;
    for (int i = 1; i <= n; i++)
        result *= i;
    return result;
}
new List<int> { 10, 50, 100, 1_000, 5_000, 10_000, 50_000, 100_000 }.ForEach(i => Console.WriteLine($"{i} -> {FacIter(i):e2}"));

// 2. rekursiv (ab 5.000 stack overflow)
static BigInteger FacRec(BigInteger n) => (n < 1) ? 1 : FacRec(n - 1) * n;
new List<int> { 10, 50, 100, 1_000, 5_000 }.ForEach(i => Console.WriteLine($"{i} -> {FacIter(i):e2}"));

/*
10 -> 3,63e+006
50 -> 3,04e+064
100 -> 9,33e+157
1000 -> 4,02e+2567
5000 -> 4,23e+16325
10000 -> 2,85e+35659
50000 -> 3,35e+213236
100000 -> 2,82e+456573
*/
                

Lösung von: Jens Kelm (@JKooP)

// C++ 14 | VS-2022
#include <iostream>
#include <functional>
#include <vector>

template<typename _Ty>
const _Ty fac_iter(_Ty n) {
    _Ty result{ 1 };
    for (_Ty i{ 1 }; i <= n; ++i) result *= i;
    return result;
}

template<typename _Ty>
const _Ty fac_rec(_Ty n) {
    return (n < 1) ? 1 : fac_rec(n - 1) * n;
}

int main() {
    std::vector<long double>v{ 10, 50, 100, 1'000 };
    for (const auto& e : v) {
        std::cout << e << " iterativ -> " << fac_iter(e) << "\n";
        std::cout << e << " rekursiv -> " << fac_rec(e) << "\n\n";
    }

}
                

Lösung von: Jens Kelm (@JKooP)