#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
	cin.tie(nullptr)->sync_with_stdio(false);
	string s;
	cin >> s;
	int n = s.size();
	s = " " + s;
	vector<int>arr(n+1);
	for(int i = 1; i<=n; i++){
		if(s[i] == 'c')arr[i] = 0;
		if(s[i] == 'd')arr[i] = 1;
		if(s[i] == 'h')arr[i] = 2;
		if(s[i] == 's')arr[i] = 3;
	}
	int ans = 0;
	vector<int>perm = {0,1,2,3};
	do{
		vector<vector<int>>dp(n+1,vector<int>(4));
		for(int i = 1; i<=n; i++){
			for(int j = 0; j<4; j++){
				for(int k = j; k<4; k++){
					dp[i][k] = max(dp[i][k],dp[i-1][j]);
				}
			}
			int idx = 0;
			for(int j = 0; j<4; j++){
				if(perm[j] == arr[i]){
					idx = j;
					break;
				}
			}
			dp[i][idx]++;
		}
		/*
		for(int nxt: perm){
			cout << nxt << ' ';
		}
		cout << '\n';
		cout << '\n';
		for(int i = 1; i<=n; i++){
			for(int j = 0; j<4; j++){
				cout << dp[i][j] << ' ';
			}
			cout << '\n';
		}
		cout << '\n';
		*/

		ans = max({ans,dp[n][0],dp[n][1],dp[n][2],dp[n][3]});
	}
	while(next_permutation(perm.begin(),perm.end()));
	cout << n-ans << '\n';
	return 0;
}