#include <iostream>
#include <vector>
#include <cstdio>
using namespace std;

using ll = long long;
using LL = long long;

#define SH(X,j) ((X|(X>>j)) & mask)

int main() {
	    ios_base::sync_with_stdio(0);
  string s;
  cin >> s;
  int L = s.size();
  ll mask = (1ll<<L)-1;
  int res = 7;

  LL num = 0;
  for (int i=0; i < s.size(); i ++) {
    num *= 2;
    num += s[i] - '0';
  }
  //cout << num << endl;

  //cout << num<< " " << mask << endl;
  
  int Lm = s.size();//(L+1) / 2 + 1;
  for (int i0=0; i0<Lm; i0++) {
    for (int i1=i0; i1<Lm; i1++) {
      for (int i2=i1; i2<Lm; i2++) {
	for (int i3=i2; i3<Lm; i3++) {
	  for (int i4=i3; i4<Lm; i4++) {
	    for (int i5=i4; i5<Lm; i5++) {
	      for (int i6=i5; i6<Lm; i6++) {

		LL v = num;
		v = SH(v, i0);
		//cout << v << endl;
		v = SH(v, i1);
		//cout << v << endl;
		v = SH(v, i2);
		//cout << v << endl;
		v = SH(v, i3);
		//cout << v << endl;
		v = SH(v, i4);
		//cout << v << endl;
		v = SH(v, i5);
		//cout << v << endl;
		v = SH(v, i6);
		//cout << i0 << " " << i1 << " " << i2<< " " << i3<< " " << i4<< " " << i5<< " " << i6 << "->" << v << endl;

		if (v == mask) {
		  int cnt = (i0!=0?1:0)+(i1!=0?1:0)+(i2!=0?1:0)+(i3!=0?1:0)+(i4!=0?1:0)+(i5!=0?1:0)+(i6!=0?1:0);
		  if (cnt < res) res = cnt;
		}
		
	      }
	    }
	  }
	}
      }
    }
  }

  cout << res << endl;
}