def return_highest(x):
    #only used once, for the first number in the answer
    x = int(x)
    if x == 1 or x == 0:
        return x
    else:
        x = x ** 0.5
        y = str(x)
        return y[:y.find('.')]

def seperate(question_s):
    # seperates the numbers before the decimal and after the decimal ( if any )
    question_string = str(question_s)
    if '.' in question_string:
        a = question_string[:question_string.find('.')]
        b = question_string[question_string.find('.')+1:]
        return(int(a),int(b))
    else:
        return(question_s,0)

def populate_z(a,b,places):
    # z[] is the array(list) that contains the number to be squarerooted(?)
    # z[] needs to be correctly populated so that the math can be done
    # the numbers need to be paired up (unlike in long division numbers are brought down in twos)
    z = ['00'] * places                                     #fill z[] with the default 0 pairs, only as many as was asked for
    a = str(a)                                              #one of the many instances of turning an int to str or visa versa
    b = str(b)
    if len(a) % 2 != 0:                                     #if there are an odd number of digits before the decimal we need to add 
        #odd number of digits                               #a zero before it, before they're grouped, so they can be grouped
        a_n = '0' + a
    else:
        a_n = a
    if len(b) % 2 != 0:
        #odd number of digits
        b_n = b + '0'
    else:
        b_n = b
    c = a_n + b_n                                           #variable c is the correctly evened out number (5.7 has become 05.70 and 23.123 has become 23.1230)
    for G in range(0,(len(c)/2)):                           #c into z[], they need to be added in pairs so that each item in the array is 2 numbers
        z[G] = c[G * 2] + c[(G * 2) + 1]
    if ( len(c) / 2) > places:                              # they asked for fewer places than they gave
        while len(z) > len(c) / 2:                          # while z (the array we use in the math) is bigger than c (evened out number)
            del z[len(z) - 1]                               # shave off what's unneccessary

    return(z)

def find_next(x,y):                                         # vital function for finding the next digit in the answer
    for a in range(0,10):
        z = int(str(x) + str(a)) * a
        z2 = int(str(x) + str(a))
        if z <= int(y):
            d = a
    return d
 
question = float(raw_input("Find the square root of: "))            # do ask? do ask.
places = int(raw_input("How many digits will the answer go to? "))
SQ = seperate(question)                                             # call seperate, makes 3.14 into [3,14] and 1234.9001 into [1234,9001]
z = populate_z(SQ[0],SQ[1],places)                                  # important step, populate z[] to use it in the math

answer = return_highest(z[0])                                       #call return highest function one and only once, to get the first digit in the answer

offnumber = int(answer) * 2                                         # offnumber is one of the significant differences between this and long division
sub = int(z[0]) - (int(answer) ** 2)                                # do the first subtraction (different because there isn't yet a tosub, because there isn't yes a nextans
added = str(sub) + z[len(str(answer))]                              # this is where we bring down the next pair of numbers in z to tack onto the end of the answer to our subtraction
nextans = str(find_next(offnumber,added))                           # here we call find_next and send it offnumber and the number it needs to be under to return the next digit in the answer
answer = answer + nextans                                           # use that next answer and tack it onto the answer

while len(str(answer)) < places:                                    # main loop, do it till the answer is populated to the number given at the beginning
    # here is the part that gave me the most trouble, the order of these is quite fragile
    # if you don't quite understand the math, just research how to do square roots by hand, this is simply an automation of exactly that
    
    tosub = int(str(offnumber) + str(nextans)) * int(nextans)
    offnumber = int(answer) * 2
    sub = int(added) - tosub
    added = str(sub) + z[len(str(answer))]
    nextans = str(find_next(offnumber,added))
    answer = answer + nextans
dec = 0

if len(str(SQ[0])) % 2 == 0:                                        # need to know where the decimal point goes
    dec = len(str(SQ[0])) / 2
else:
    dec = (len(str(SQ[0]))+1) / 2


finalanswer = str(answer[0:dec]) + '.' + str(answer[dec:])          # we need to add the decimal point back in since the math is done

print finalanswer