package com.javarush.task.task04.task0424;

/*
Три числа
*/

import java.io.*;
import java.util.Arrays;

public class Solution {
    public static void main(String[] args) throws Exception {
        int[] arr = new int[3];
        int x = 0;
        for (int i = 0; i < arr.length; i++) {
            BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
            String sDigit = reader.readLine();
            int digit = Integer.parseInt(sDigit);
            arr[x] = (digit);
            x++;
        }
        if (arr[0] != arr[1] && arr[1] == arr[2]) System.out.println(1);
        if (arr[1] != arr[2] && arr[0] == arr[2]) System.out.println(2);
        if (arr[2] != arr[0] && arr[0] == arr[1]) System.out.println(3);
    }
}