import java.util.*;

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