import java.io.*;
import java.util.StringTokenizer;

public final class Main{
    public static void main(String[] args){
        FastScanner stdIn = new FastScanner(System.in);
        long a = stdIn.nextLong();
        long b = stdIn.nextLong();
        long c = stdIn.nextLong();

        if(c-(a-b)<0){
            System.out.println(0);
        }else{
            System.out.println(c-(a-b));
        }
    }
}

class FastScanner {
    private BufferedReader reader = null;
    private StringTokenizer tokenizer = null;

    public FastScanner(InputStream in) {
        reader = new BufferedReader(new InputStreamReader(in));
        tokenizer = null;
    }

    public String next() {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

    public String nextLine() {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                return reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        return tokenizer.nextToken("\n");
    }

    public long nextLong() {
        return Long.parseLong(next());
    }
    
    public long nextInt() {
        return Integer.parseInt(next());
    }

} import java.io.*; io.* java import java.util.StringTokenizer; StringTokenizer java.util public final class Main{
    public static void main(String[] args){
        FastScanner stdIn = new FastScanner(System.in);
        long a = stdIn.nextLong();
        long b = stdIn.nextLong();
        long c = stdIn.nextLong();

        if(c-(a-b)<0){
            System.out.println(0);
        }else{
            System.out.println(c-(a-b));
        }
    }
} Main public static void main(String[] args){
        FastScanner stdIn = new FastScanner(System.in);
        long a = stdIn.nextLong();
        long b = stdIn.nextLong();
        long c = stdIn.nextLong();

        if(c-(a-b)<0){
            System.out.println(0);
        }else{
            System.out.println(c-(a-b));
        }
    } main {
        FastScanner stdIn = new FastScanner(System.in);
        long a = stdIn.nextLong();
        long b = stdIn.nextLong();
        long c = stdIn.nextLong();

        if(c-(a-b)<0){
            System.out.println(0);
        }else{
            System.out.println(c-(a-b));
        }
    } FastScanner stdIn = new FastScanner(System.in); stdIn new FastScanner(System.in) long a = stdIn.nextLong(); a stdIn.nextLong() stdIn.nextLong stdIn long b = stdIn.nextLong(); b stdIn.nextLong() stdIn.nextLong stdIn long c = stdIn.nextLong(); c stdIn.nextLong() stdIn.nextLong stdIn if(c-(a-b)<0){
            System.out.println(0);
        }else{
            System.out.println(c-(a-b));
        } c-(a-b)<0 c-(a-b) c (a-b) a b 0 {
            System.out.println(0);
        } System.out.println(0) System.out.println System.out System System.out 0 {
            System.out.println(c-(a-b));
        } System.out.println(c-(a-b)) System.out.println System.out System System.out c-(a-b) c (a-b) a b String[] args args class FastScanner {
    private BufferedReader reader = null;
    private StringTokenizer tokenizer = null;

    public FastScanner(InputStream in) {
        reader = new BufferedReader(new InputStreamReader(in));
        tokenizer = null;
    }

    public String next() {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

    public String nextLine() {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                return reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        return tokenizer.nextToken("\n");
    }

    public long nextLong() {
        return Long.parseLong(next());
    }
    
    public long nextInt() {
        return Integer.parseInt(next());
    }

} FastScanner private BufferedReader reader = null; reader null private StringTokenizer tokenizer = null; tokenizer null public FastScanner(InputStream in) {
        reader = new BufferedReader(new InputStreamReader(in));
        tokenizer = null;
    } FastScanner {
        reader = new BufferedReader(new InputStreamReader(in));
        tokenizer = null;
    } reader = new BufferedReader(new InputStreamReader(in)) reader new BufferedReader(new InputStreamReader(in)) tokenizer = null tokenizer null InputStream in in public String next() {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    } next {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    } if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        } tokenizer == null || !tokenizer.hasMoreTokens() tokenizer == null tokenizer null !tokenizer.hasMoreTokens() tokenizer.hasMoreTokens() tokenizer.hasMoreTokens tokenizer {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        } try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            } catch (IOException e) {
                throw new RuntimeException(e);
            } IOException e {
                throw new RuntimeException(e);
            } throw new RuntimeException(e); new RuntimeException(e) {
                tokenizer = new StringTokenizer(reader.readLine());
            } tokenizer = new StringTokenizer(reader.readLine()) tokenizer new StringTokenizer(reader.readLine()) return tokenizer.nextToken(); tokenizer.nextToken() tokenizer.nextToken tokenizer public String nextLine() {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                return reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        return tokenizer.nextToken("\n");
    } nextLine {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                return reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        return tokenizer.nextToken("\n");
    } if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                return reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        } tokenizer == null || !tokenizer.hasMoreTokens() tokenizer == null tokenizer null !tokenizer.hasMoreTokens() tokenizer.hasMoreTokens() tokenizer.hasMoreTokens tokenizer {
            try {
                return reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        } try {
                return reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            } catch (IOException e) {
                throw new RuntimeException(e);
            } IOException e {
                throw new RuntimeException(e);
            } throw new RuntimeException(e); new RuntimeException(e) {
                return reader.readLine();
            } return reader.readLine(); reader.readLine() reader.readLine reader return tokenizer.nextToken("\n"); tokenizer.nextToken("\n") tokenizer.nextToken tokenizer "\n" public long nextLong() {
        return Long.parseLong(next());
    } nextLong {
        return Long.parseLong(next());
    } return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next public long nextInt() {
        return Integer.parseInt(next());
    } nextInt {
        return Integer.parseInt(next());
    } return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next public final class Main{
    public static void main(String[] args){
        FastScanner stdIn = new FastScanner(System.in);
        long a = stdIn.nextLong();
        long b = stdIn.nextLong();
        long c = stdIn.nextLong();

        if(c-(a-b)<0){
            System.out.println(0);
        }else{
            System.out.println(c-(a-b));
        }
    }
} public final class Main{
    public static void main(String[] args){
        FastScanner stdIn = new FastScanner(System.in);
        long a = stdIn.nextLong();
        long b = stdIn.nextLong();
        long c = stdIn.nextLong();

        if(c-(a-b)<0){
            System.out.println(0);
        }else{
            System.out.println(c-(a-b));
        }
    }
} Main
import java.io.*;
import java.util.StringTokenizer;

public final class Main{
    public static void main(String[] args){
        FastScanner stdIn = new FastScanner(System.in);
        long a = stdIn.nextLong();
        long b = stdIn.nextLong();
        long c = stdIn.nextLong();

        if(c-(a-b)<0){
            System.out.println(0);
        }else{
            System.out.println(c-(a-b));
        }
    }
}

class FastScanner {
    private BufferedReader reader = null;
    private StringTokenizer tokenizer = null;

    public FastScanner(InputStream in) {
        reader = new BufferedReader(new InputStreamReader(in));
        tokenizer = null;
    }

    public String next() {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

    public String nextLine() {
        if (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                return reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }

        return tokenizer.nextToken("\n");
    }

    public long nextLong() {
        return Long.parseLong(next());
    }
    
    public long nextInt() {
        return Integer.parseInt(next());
    }

}
