#include<stdio.h>
int main()
{
    float initial bal;
    scanf(".2%f",&initial bal);
    int n;
    scanf("%d",&n);
    float trans a;
    scanf(".2%f",&trans a);
    float trans b;
    scanf(".2%f",&trans b);
    float trans c;
    scanf(".2%f",&trans c);
    float final balance;
    final balance=initial bal-trans a-trans b-trans c;
    printf("final balance=",final balance);
    return 0;
}