import java.util.*;
public class Main {
    public static void main(String[] args){
     Scanner s=new Scanner(System.in);
     int A=s.nextInt();
     int B=s.nextInt();
     int C=s.nextInt();
     int ans=C-(A-B);
     if(ans<0)
         System.out.println(0);
     else {
         System.out.print(ans);
     }
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz