from decimal import *
import sys

sys.setrecursionlimit(10 ** 6)
int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")
def MI(): return map(int, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]

def main():
    n=int(input())
    aa=[]
    for _ in range(n):
        s=input()
        if "." in s:aa.append(Decimal(s))
        else:aa.append(int(s))
    print(format(sum(aa),".10f"))


main()