import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long y = sc.nextLong();
		long z = sc.nextLong();
		sc.close();

		long ans = z;
		if (x <= z) ans--;
		if (y <= z) ans--;
		System.out.println(ans);
	}
}