import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] ws = W.split(" ");
		int A = Integer.parseInt(ws[0]);
		int B = Integer.parseInt(ws[1]);
		int C = Integer.parseInt(ws[2]);

		int x = A-B;
		int y = C-x;
		if(y<=0){
			y=0;
		}
		System.out.println(y);


	}

} import java.io.BufferedReader; BufferedReader java.io import java.io.InputStreamReader; InputStreamReader java.io public class Main {

	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] ws = W.split(" ");
		int A = Integer.parseInt(ws[0]);
		int B = Integer.parseInt(ws[1]);
		int C = Integer.parseInt(ws[2]);

		int x = A-B;
		int y = C-x;
		if(y<=0){
			y=0;
		}
		System.out.println(y);


	}

} Main public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] ws = W.split(" ");
		int A = Integer.parseInt(ws[0]);
		int B = Integer.parseInt(ws[1]);
		int C = Integer.parseInt(ws[2]);

		int x = A-B;
		int y = C-x;
		if(y<=0){
			y=0;
		}
		System.out.println(y);


	} main {
		// TODO 自動生成されたメソッド・スタブ
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] ws = W.split(" ");
		int A = Integer.parseInt(ws[0]);
		int B = Integer.parseInt(ws[1]);
		int C = Integer.parseInt(ws[2]);

		int x = A-B;
		int y = C-x;
		if(y<=0){
			y=0;
		}
		System.out.println(y);


	} BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); in new BufferedReader(new InputStreamReader(System.in)) String W = in.readLine(); W in.readLine() in.readLine in String[] ws = W.split(" "); ws W.split(" ") W.split W " " int A = Integer.parseInt(ws[0]); A Integer.parseInt(ws[0]) Integer.parseInt Integer ws[0] ws 0 int B = Integer.parseInt(ws[1]); B Integer.parseInt(ws[1]) Integer.parseInt Integer ws[1] ws 1 int C = Integer.parseInt(ws[2]); C Integer.parseInt(ws[2]) Integer.parseInt Integer ws[2] ws 2 int x = A-B; x A-B A B int y = C-x; y C-x C x if(y<=0){
			y=0;
		} y<=0 y 0 {
			y=0;
		} y=0 y 0 System.out.println(y) System.out.println System.out System System.out y String[] args args public class Main {

	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] ws = W.split(" ");
		int A = Integer.parseInt(ws[0]);
		int B = Integer.parseInt(ws[1]);
		int C = Integer.parseInt(ws[2]);

		int x = A-B;
		int y = C-x;
		if(y<=0){
			y=0;
		}
		System.out.println(y);


	}

} public class Main {

	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] ws = W.split(" ");
		int A = Integer.parseInt(ws[0]);
		int B = Integer.parseInt(ws[1]);
		int C = Integer.parseInt(ws[2]);

		int x = A-B;
		int y = C-x;
		if(y<=0){
			y=0;
		}
		System.out.println(y);


	}

} Main
import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {

	public static void main(String[] args) throws Exception {
		// TODO 自動生成されたメソッド・スタブ
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		String W = in.readLine();
		String[] ws = W.split(" ");
		int A = Integer.parseInt(ws[0]);
		int B = Integer.parseInt(ws[1]);
		int C = Integer.parseInt(ws[2]);

		int x = A-B;
		int y = C-x;
		if(y<=0){
			y=0;
		}
		System.out.println(y);


	}

}
