#include<cstdio>
#include<cstring>

//int sep=" /-"
char s[100000];
/*
void cit(int &k, int &l)
{
	char x,y;
	k=0;l=0;
	int p;
	
	scanf("%c",&x);
	while(int(x)>=122 || (int(x)<=97&&int(x)>=90) || int(x)<=65)
		scanf("%c",&x);
	while(!feof(stdin))
	{
		if( (97<=int(x)&&int(x)<=122) || (65<=int(x)&&int(x)<=90))
			++l;
		else
			++k;
		scanf("%c",&y);
		p=0;
		
		while( ( int(x)>122 || (int(x)<97&&int(x)>90) || int(x)<65 ) && ( int(y)>122 || (int(y)<97&&int(y)>90) || int(y)<65 ) &&!feof(stdin) )
		{
			x=y;
			scanf("%c",&y);
			++p;
		}
		/*if(p)
			l--;*/
/*		x=y;
	}
}
*/
void cit(int &k, int &l)
{
	int i;
	fgets(s,100000,stdin);
	k=0;l=0;
	i=0;
	while( ( int(s[i])>122 || (int(s[i])<97&&int(s[i])>90) || int(s[i])<65 ) )
		i++;
	
	for(; s[i]; i++)
	{
		if( (int('a')<=int(s[i]) && int(s[i])<=int('z')) || (int('A')<=int(s[i]) && int(s[i])<=int('Z')) )
			l++;
		else
			k++;
		
		while( ( ( int(s[i])>122 || (int(s[i])<97&&int(s[i])>90) || int(s[i])<65 ) && ( int(s[i+1])>122 || (int(s[i+1])<97&&int(s[i+1])>90) || int(s[i+1])<65  ) ) &&s[i] )
			++i;
	}
	
}

void afis(int k, int l)
{
	printf("%d",l/k);
}



int main()
{
	freopen("text.in","r",stdin);
	freopen("text.out","w",stdout);
	
	int k,l;
	
	
	cit(k,l);
	afis(k,l);
}