#include<stdio.h>

#include<iostream>

#define N 10000000

using namespace std;





long long solve()
{
	freopen("text.in","r",stdin);
	int litere=0,cuvinte=0;
	char ch,cch;
	while(scanf("%c",&ch)!=EOF)
	{
		if((cch<'A' || cch>'Z' && cch<'a' || cch>'z') && (ch>='A' && ch<='Z' || ch>='a' && ch<='z'))
			++cuvinte;
		if((ch>='A' && ch<='Z' || ch>='a' && ch<='z') && (cch>='A' && cch<='Z' || cch>='a' && cch<='z'))
			++litere;
	}
	return litere/cuvinte;
}
void afisare()
{
	freopen("text.out","w",stdout);
	printf("%lld",solve());
}
int main()
{
	solve();
	afisare();
	return 0;
}