package backjoon;

// https://www.acmicpc.net/problem/2231

// 분해합

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

public class _2231 {

public static void main(String[] args) throws IOException {

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

// memory 11484 runtime 88

int N = Integer.parseInt(br.readLine());

int min = 0;

for(int i = 0; i < N; i++) {

int number = i;

int sum = 0; // 각 자릿수 합 변수

while(number != 0) {

// System.out.println("number: "+number+" , "+number%10 +" , "+number/10 + ", sum: "+sum);

sum += number % 10; // 각 자릿수 더하기

number /= 10;

}

if(sum + i == N) {

min = i;

break;

}

}

System.out.println(min);

}

}

/*

input

216

output

198

*/