import java.util.*;

public class Main{
  public static void main(String args[]){
    Scanner scanner = new Scanner(System.in);
    long x = scanner.nextLong();
    long y = scanner.nextLong();
    long z = scanner.nextLong();
    long ans = z;
    if(z >= x){
      ans -= 1;
    }
    if(z >= y){
      ans -= 1;
    }
    System.out.println(ans);
  }
}