#include<bits/stdc++.h> 
using namespace std;
int main(){
	ios::sync_with_stdio(false);
	char s[100000];
	cin>>s;
	int n=strlen(s);
	int ans=0;
	for(int i=0;i<n;i++){
		if(s[i]>='A'&&s[i]<='Z')
		ans++;
		if(s[i]>='a'&&s[i]<='z')
		ans++;
		if(s[i]>='0'&&s[i]<='9')
		ans++;
	}
	cout<<ans;
	return 0;
}