#include<bits/stdc++.h>
#define Add(x,y) (x+y>=mod)?(x+y-mod):(x+y)
#define lowbit(x) x&(-x)
#define pi pair<ll,ll>
#define pii pair<ll,pair<ll,ll>>
#define iip pair<pair<ll,ll>,ll>
#define ppii pair<pair<ll,ll>,pair<ll,ll>>
#define fi first
#define se second
#define full(l,r,x) for(auto it=l;it!=r;it++) (*it)=x
#define Full(a) memset(a,0,sizeof(a))
#define open(s1,s2) freopen(s1,"r",stdin),freopen(s2,"w",stdout);
#define For(i,l,r) for(register int i=l;i<=r;i++)
#define _For(i,l,r) for(register int i=r;i>=l;i--)
using namespace std;
typedef double db;
typedef unsigned long long ull;
typedef long long ll;
bool Begin;
const ll N=1e6+10; 
inline ll read(){
    ll x=0,f=1;
    char c=getchar();
    while(c<'0'||c>'9'){
        if(c=='-')
          f=-1;
        c=getchar();
    }
    while(c>='0'&&c<='9'){
        x=(x<<1)+(x<<3)+(c^48);
        c=getchar();
    }
    return x*f;
}
inline void write(ll x){
	if(x<0){
		putchar('-');
		x=-x;
	}
	if(x>9)
	  write(x/10);
	putchar(x%10+'0');
}
ll n,ans;
ll a[N];
char s[N];
vector<ll> v;
ll get(){
	ll sum=0;
	n=v.size();
	_For(i,0,n-1){
		sum=sum*10ll+v[i];
		a[i]=sum>>1;
		sum%=2;
	}
	while(n&&!a[n-1])
	  n--;
	v.clear();
	For(i,0,n-1)
	  v.push_back(a[i]);
	return sum;
}
bool End;
int main(){
	scanf("%s",s);
	n=strlen(s);
	For(i,0,n-1)
	  v.push_back(s[i]-'0');
	reverse(v.begin(),v.end());
	while(v.size())
	  ans+=get();
	write(ans);
	cerr<<'\n'<<abs(&Begin-&End)/1048576<<"MB";
	return 0;
}