def first_Digit(n) :
    import math 
     
    fact = 1
    for i in range(2,n + 1) : 
        fact = fact * i 
        while (fact % 10 == 0) :  
            fact = int(fact / 10) 
    while (fact >= 10) : 
        fact = int(fact / 10) 
    return math.floor(fact) 
def first_Digit(n):
    import math
    fact = 1
    i = 2
    while i < n + 1:
        fact = fact * i
       
        while fact % 10 == 0:
            fact = int(fact / 10)
        i += 1
    while fact >= 10:
        fact = int(fact / 10)
    return math.floor(fact)