#include<bits/stdc++.h>
using namespace std;
int main(){
    int a,b,c,d,e;
    cin>>a;
    b=a%10*1000;
    c=a/10%10*100;
    d=a/100%10*10;
    e=a/1000%10;
    b=b+c+d+e;
    a=a-b;
    cout<<a;
}
/**************************************************************
	Problem: 1702
	User: wengsihan
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/