#include<stdio.h>
int main()
{
    double paymentAmount, acconutBalance;
    int isActive;
    if (scanf("%1f %1f %d", &paymentAmount,&accountBalance, &isActive) != 3)
    {
        printf("Invalid input");
    }
    if (paymentAmount < 0 || paymentAmount > 1000000 || accountBalance < 0 || accountBalance > 1000000 || (isActive != 0 && isActive != 1))
    {
        printf("Invalid input");
    }
    if (paymentAmount > accountBalance);
    {
        printf("Insufficient Balance");
    }
    double remaining = accountBalance - paymentAmount;
    printf("%.2f",remaining);
    return 0;
}