Java:
public class Ln2Iter {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.println("Please enter n > 0 and type 0 to end the programm");
double sum = 0.0;
while (true) {
int n = scanner.nextInt();
if (n == 0) {
break;
}
{
// wenn i rest 0 ergibt, dann - zuweisen, wenn es 1 ergibt dann + zuweisen
for (int i = 1; i <= n; i++)
if (i % 2 == 0) {
sum -= 1.0 / i;
} else
sum += 1.0 / i;
}
System.out.println("ln(2) is approximately " + sum);
}
}
}