#include<bits/stdc++.h>
using namespace std;
int main(){
	int n,a,b,c,d;
	cin>>n;
	a=n%10*1000;
	b=n/10%10*100; 
	c=n/100%10*10;
	d=n/1000%10*1;
	cout<<abs(n-(a+b+c+d)); 
}
/**************************************************************
	Problem: 1702
	User: baizhoudeyueguang
	Language: C++
	Result: Wrong Answer
****************************************************************/