#include <iostream>
#include <string>
#include <sstream>

using namespace std;
int main()
{
string str;
while (getline(cin, str))
{
istringstream instr(str);
double sum = 0;
while (instr >> str)
{
int pos = str.find(':', 0);
int num = atoi(str.substr(0, pos).c_str());
double num2 = atof(str.substr(pos + 1, str.length()).c_str());
num % 2 != 0 ? sum += num2 : sum -= num2;
}
cout << sum << endl;
}
return 0;
}