#include<stdio.h>
int main()
{
    int a,b,c;
    float d;
    scanf("%d",&a);
    scanf("%d",&b);
    scanf("%d",&c);
    if(a!=1||b!=1||c!=1)
        printf("Invalid input");
        return 0;
    if(a<0||a>1000000||b<0||b>1000000||c!=0&&c!=1){
        printf("invalid input");}
    if(c==0){    
         printf("Account is invalid");}
    if(a>b){
        printf("Insufficient Balance");
    float d=b-a;
    printf("%.2f",d);
    return 0;
}