asdasd

from decimal import *

def remove_exponent(d):
    return d.quantize(Decimal(1)) if d == d.to_integral() else d.normalize()

getcontext().prec = 20

inp = input()
a = inp.split(' ')
array_ = []
sum_ = Decimal('0')
c = int(0)
len_ = -9999
for i in a:
    ar_ = a[c].split('.')
    len__ = len(str(ar_[1]))
    len_ = len__ if (len_<len__) else len_
    c = c+1

c = int(0)
for i in a:
    sum_ += Decimal(str(a[c]))
    c=c+1
print('{0:f}'.format(sum_))