using namespace std;
double sum,x,y;
string ten;
int main(){
	freopen("cart.in","r",stdin);
	freopen("cart.out","w",stdout);
    while(scanf("%s %lf ### %lf",ten.c_str(),&x,&y)!=EOF){
        sum+=x*y;
    }
    printf("%.2lf",sum);
}