#include<stdio.h>
#include<ctype.h>
#include<string.h>
struct Order {
    char productName[51];
    int productID;
    float price;
};
int isValidName(char name[]) {
    for (int i = 0;name[i] != '\0',i++){
        if (!isalnum(name[i])) {
            return 0;
        }
    }
    return 1;
}

int main() {
    int n;
    scanf("%d", &n);
    
    if(n < 0) {
        printf("Invalid input\n");
        return 0;
    }
    
    struct Order order[10];
    float total = 0;
    
    for (int i = 0; i < n; i++) {
        scanf("%s %d %f", order[i].productName, &orders[i].productID, &orders[i].price);
        
        if(!isValidName(order[i].productName)) {
            printf("Inavlid input\n");
            return 0;
        }
        
        total += order[i].price;
    }
    printf("%.2f/n",total);
}