import java.util.*;

public class Main {
	public static void main (String[] args) {
		Scanner sc = new Scanner(System.in);
		long x = sc.nextLong();
		long y = sc.nextLong();
		long z = sc.nextLong();
		long count = z;
		if (x <= z) {
		    count--;
		}
		if (y <= z) {
		    count--;
		}
		System.out.println(count);
	}
}