#include <bits/stdc++.h>

using namespace std;

std::ostream&
operator<<( std::ostream& dest, __int128_t value )
{
    std::ostream::sentry s( dest );
    if ( s ) {
        __uint128_t tmp = value < 0 ? -value : value;
        char buffer[ 128 ];
        char* d = std::end( buffer );
        do
        {
            -- d;
            *d = "0123456789"[ tmp % 10 ];
            tmp /= 10;
        } while ( tmp != 0 );
        if ( value < 0 ) {
            -- d;
            *d = '-';
        }
        int len = std::end( buffer ) - d;
        if ( dest.rdbuf()->sputn( d, len ) != len ) {
            dest.setstate( std::ios_base::badbit );
        }
    }
    return dest;
}

int main(void)
{
	cin.tie(0);
	ios::sync_with_stdio(false);
	
	__int128 sum = 0;
	int n;
	string s;
	cin >> n;

	for (int i = 0; i < n; i++)
	{
		cin >> s;
		string a,b;
		for(int j=0;j<s.length();j++)
		{
			if(s[j]=='.')
			{
				a = s.substr(0,j);
				b = s.substr(j+1);
				break;
			}
		}
		if(a=="") a = s;
		while(b.length()<10)
		{
			b += '0';
		}
		a += b;
		__int128 temp = 0;
		__int128 num = 1;
		for(int j=a.length()-1;j>=0;j--)
		{
			if(a[j]=='-') continue;
			temp += ((a[j]-'0')*num);
			num*=10;
		}
		if(a[0]=='-')
		{
			temp*=-1;
		}
		sum += temp;
	}


	string res;
	__int128 temp = abs(sum);
	while(temp > 0)
	{
		res = (char)(temp%10 + '0') + res;
		temp/=10;
		if(res.length()==10)
		{
			res = '.' + res;
		}
	}
	
	if(res.length()<10)
	{
		while(res.length()<10)
		{
			res = '0' + res;
		}
		res = "0." + res;
	}
	
	if(res[0]=='.')
	{
		res = '0' + res;
	}
		
	if(sum < 0)
	{
		res = '-' + res;
	}
	
	cout << res << '\n';
	return 0;
}