
package lianxi;
import java.util.*;
public class Main {
public static void main(String args[]) {
Scanner scan = new Scanner(System.in);
String line;
while (scan.hasNextLine()) {
line = scan.nextLine().trim();
List<String> list = Arrays.asList(line.split(","));///返回由指定数组支持的固定大小的列表。
int i = 1;
while (true){
if(!list.contains(i+"")){///判断是否包含某元素
break;
}
i++;
}
System.out.println(i);
}
}
}