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

int main()
{
	char s[10];
	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;
}