#include "bits/stdc++.h"

using namespace std;

int main () {
	/*
//				 01234567
	 string s = "abcdefgh";
	 */
	 //int n = s.size(); //size of string
	 /*
	 for (int i = 0; i < n; ++i) {
		 cout << s[i];
	 }
	 */
	 /*
	 //char strs[6] = {'a', 'b', 'c', 'd', 'e', 'f'};
	 //s = s + "abcd"; //concatination //
	 //cout << s << '\n';
	 s.push_back('a'); //O(1) // abcdefgha //insert
	 //cout << s << '\n';                //01234567
	 s.pop_back(); //erase last element // abcdefgh
	 //cout << s << '\n';
	 s.erase(7, 2); // starting_pos, count
	 cout << s << '\n';
	 */
	 /*
	 string s;
	 //cin >> s;
	 //cout << s << endl;
	 //getline(cin, s);
	 cout << s << endl;
	 */       // 01234567
	 string s = "abcdeghh";

	 //string::iterator begin = s.begin();
	 //string::iterator end = s.end();
	 /*
	 auto begin = s.begin();
	 cout << *begin << endl;
	 s.erase(s.begin(), s.end()); //starting iterator, ending iterator
	 cout << s << endl;
	 */
	 /*
	 int count = 0;
	 int n = s.size();
	 for (int i = 0; i < n; ++i) {
		 if (s[i] == 'h') {
			 count++;
		 }
	 }
	 cout << count << endl;
	 */
	 cout << count(s.begin() + 1, s.end(), 'a'); //count => (starting iterator, ending iterator, search character)
}

//https://codeforces.com/problemset/problem/1146/A
//https://codeforces.com/problemset/problem/71/A
//https://codeforces.com/problemset/problem/112/A
//https://codeforces.com/problemset/problem/339/A
//https://codeforces.com/problemset/problem/281/A