#include <stdio.h>
#include <string.h>
#include <ctype.h>

struct Order {
    char productName[100];
    int productID;
    double price;
};
int isValidName(char name[]) {
    for (int i = 0; name[i] != '\0'; i++){
        if (!isalpha(name[i]) && !isspace(name[i])) {
            return 0;
        }
    }
    return 1;
}
int main(){
    int n;
    if (scanf("%d", &n) != 1 || n <= 0) {
        printf("Invalid input");
        return 0;
    }
    struct Order orders[n];
    double total = 0;
    
    for (int i = 0; i < n; i++) {
        getchar();
        if (scanf("%[^\n]", orders[i].productName) !=1) {
            printf("Invalid input");
            return 0;
        }
        if (!i ValidName (orders[i].productName)) {
            printf("Invalid input");
            return 0;
        }
        if (scanf("%d", &orders[i].price) !=1) {
            printf("Invalid input");
            return 0;
        }
        if (scanf("%lf", &orders[i].price) !=1) {
            printf("Invalid input");
            return 0;
        }
        total += orders[i].price;
    }
    printf("%.2lf", total);
    return 0;
}