import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

class Main {
	
    public static void main(String[] args) {
		OriginScanner os = new OriginScanner();
		PrintWriter pw = new PrintWriter(System.out);
		
		int a = os.nextInt();
		int b = os.nextInt();
		int c = os.nextInt();
		
		int diff = a - b;
		
		int min = Math.min(diff, c);
		
		pw.println(c - min);
		pw.close();
	}
    
	static class OriginScanner {
		StringTokenizer token;
		BufferedReader br;
		
		public OriginScanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		
		String nextLine() {
			String str = null;
			try {
				str = br.readLine();
			}
			catch (IOException e) {
				System.out.println(e);
			}
			return str;
		}
		
		String next() {
			while (token == null || !token.hasMoreElements()) { 
				token = new StringTokenizer(nextLine());
			}
			return token.nextToken();
		}
		
		int nextInt() {
			return Integer.parseInt(next());
		}
		
		long nextLong() {
			return Long.parseLong(next());
		}
	}
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io import java.io.PrintWriter; PrintWriter java.io import java.util.StringTokenizer; StringTokenizer java.util class Main {
	
    public static void main(String[] args) {
		OriginScanner os = new OriginScanner();
		PrintWriter pw = new PrintWriter(System.out);
		
		int a = os.nextInt();
		int b = os.nextInt();
		int c = os.nextInt();
		
		int diff = a - b;
		
		int min = Math.min(diff, c);
		
		pw.println(c - min);
		pw.close();
	}
    
	static class OriginScanner {
		StringTokenizer token;
		BufferedReader br;
		
		public OriginScanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		
		String nextLine() {
			String str = null;
			try {
				str = br.readLine();
			}
			catch (IOException e) {
				System.out.println(e);
			}
			return str;
		}
		
		String next() {
			while (token == null || !token.hasMoreElements()) { 
				token = new StringTokenizer(nextLine());
			}
			return token.nextToken();
		}
		
		int nextInt() {
			return Integer.parseInt(next());
		}
		
		long nextLong() {
			return Long.parseLong(next());
		}
	}
} Main public static void main(String[] args) {
		OriginScanner os = new OriginScanner();
		PrintWriter pw = new PrintWriter(System.out);
		
		int a = os.nextInt();
		int b = os.nextInt();
		int c = os.nextInt();
		
		int diff = a - b;
		
		int min = Math.min(diff, c);
		
		pw.println(c - min);
		pw.close();
	} main {
		OriginScanner os = new OriginScanner();
		PrintWriter pw = new PrintWriter(System.out);
		
		int a = os.nextInt();
		int b = os.nextInt();
		int c = os.nextInt();
		
		int diff = a - b;
		
		int min = Math.min(diff, c);
		
		pw.println(c - min);
		pw.close();
	} OriginScanner os = new OriginScanner(); os new OriginScanner() PrintWriter pw = new PrintWriter(System.out); pw new PrintWriter(System.out) int a = os.nextInt(); a os.nextInt() os.nextInt os int b = os.nextInt(); b os.nextInt() os.nextInt os int c = os.nextInt(); c os.nextInt() os.nextInt os int diff = a - b; diff a - b a b int min = Math.min(diff, c); min Math.min(diff, c) Math.min Math diff c pw.println(c - min) pw.println pw c - min c min pw.close() pw.close pw String[] args args static class OriginScanner {
		StringTokenizer token;
		BufferedReader br;
		
		public OriginScanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		
		String nextLine() {
			String str = null;
			try {
				str = br.readLine();
			}
			catch (IOException e) {
				System.out.println(e);
			}
			return str;
		}
		
		String next() {
			while (token == null || !token.hasMoreElements()) { 
				token = new StringTokenizer(nextLine());
			}
			return token.nextToken();
		}
		
		int nextInt() {
			return Integer.parseInt(next());
		}
		
		long nextLong() {
			return Long.parseLong(next());
		}
	} OriginScanner StringTokenizer token; token BufferedReader br; br public OriginScanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
		} OriginScanner {
			br = new BufferedReader(new InputStreamReader(System.in));
		} br = new BufferedReader(new InputStreamReader(System.in)) br new BufferedReader(new InputStreamReader(System.in)) String nextLine() {
			String str = null;
			try {
				str = br.readLine();
			}
			catch (IOException e) {
				System.out.println(e);
			}
			return str;
		} nextLine {
			String str = null;
			try {
				str = br.readLine();
			}
			catch (IOException e) {
				System.out.println(e);
			}
			return str;
		} String str = null; str null try {
				str = br.readLine();
			}
			catch (IOException e) {
				System.out.println(e);
			} catch (IOException e) {
				System.out.println(e);
			} IOException e {
				System.out.println(e);
			} System.out.println(e) System.out.println System.out System System.out e {
				str = br.readLine();
			} str = br.readLine() str br.readLine() br.readLine br return str; str String next() {
			while (token == null || !token.hasMoreElements()) { 
				token = new StringTokenizer(nextLine());
			}
			return token.nextToken();
		} next {
			while (token == null || !token.hasMoreElements()) { 
				token = new StringTokenizer(nextLine());
			}
			return token.nextToken();
		} while (token == null || !token.hasMoreElements()) { 
				token = new StringTokenizer(nextLine());
			} token == null || !token.hasMoreElements() token == null token null !token.hasMoreElements() token.hasMoreElements() token.hasMoreElements token { 
				token = new StringTokenizer(nextLine());
			} token = new StringTokenizer(nextLine()) token new StringTokenizer(nextLine()) return token.nextToken(); token.nextToken() token.nextToken token int nextInt() {
			return Integer.parseInt(next());
		} nextInt {
			return Integer.parseInt(next());
		} return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next long nextLong() {
			return Long.parseLong(next());
		} nextLong {
			return Long.parseLong(next());
		} return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

class Main {
	
    public static void main(String[] args) {
		OriginScanner os = new OriginScanner();
		PrintWriter pw = new PrintWriter(System.out);
		
		int a = os.nextInt();
		int b = os.nextInt();
		int c = os.nextInt();
		
		int diff = a - b;
		
		int min = Math.min(diff, c);
		
		pw.println(c - min);
		pw.close();
	}
    
	static class OriginScanner {
		StringTokenizer token;
		BufferedReader br;
		
		public OriginScanner() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		
		String nextLine() {
			String str = null;
			try {
				str = br.readLine();
			}
			catch (IOException e) {
				System.out.println(e);
			}
			return str;
		}
		
		String next() {
			while (token == null || !token.hasMoreElements()) { 
				token = new StringTokenizer(nextLine());
			}
			return token.nextToken();
		}
		
		int nextInt() {
			return Integer.parseInt(next());
		}
		
		long nextLong() {
			return Long.parseLong(next());
		}
	}
}