#include<bits/stdc++.h>
using namespace std;

const long long INF = 1LL << 60;
#define MOD 1000000007;

typedef long long ll;

#define writeln(n) cout<<n<<endl;

typedef pair<float, float> P;

typedef pair<string, int> Psi;


int main() {

	string s;
	cin>>s;

	int cnt=0;
	for(int i=0; i<s.size(); i++){
		if(s[i] =='0')cnt++;
	}
	
	writeln(abs(8-cnt));

}