code:
#include<bits/stdc++.h>
using namespace std;
const int N=2e5+55; //max range 10^9
int cnt;
string str;
int main()
{
cin>>str;
for(int i=0;str[i]!='\0';i++)
{
if(str[i]>=0 || str[i]<=9)
{
cnt++;
}
}
cout<<cnt<<endl;
return 0;
}