// Count the number of letters (lowercase or uppercase) in a string.
#include <iostream>
#include <string>
using namespace std;
int main()
{
	string s;
	int i, n, count;
	cout << "Enter a string: \n";
	getline(cin,s);
	n = s.length();
	count = 0;
	i = 0;
	while (i < n)
	{
		if (toupper(s[i]) >= 'A' && toupper(s[i]) <= 'Z')
		//if (s[i] >= 'a' && s[i] <= 'z')
		if ((s[i] >= 'a' && s[i] <= 'z') || (s[i] >= 'A' && s[i] <= 'Z'))
			count++;
		i++;
	}
	cout << count << endl;
	return 0;
}