Create Task 13

/* Task 13. Write a program that calculates for given N how many trailing zeros present at the end of the number N!. 
 * Examples:N = 10  N! = 3628800  2N = 20  N! = 2432902008176640000  4 Does your program work for N = 50 000? 
 * Hint: The trailing zeros in N! are equal to the number of its prime divisors of value 5. Think why!*/