#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

	string s, goal;
	cin >> s;
	goal = s;
	sort(goal.begin(), goal.end());

	map<string, int> m;
	m[s] = 0;
	queue<string> q;
	q.push(s);
	while(q.size()) {
		s = q.front();
		q.pop();
		int d = m[s];
		for(int i = 0; i < s.size() - 1; i++) {
			string ns = s;
			swap(ns[i], ns[i + 1]);
			if(m.count(ns)) continue;
			m[ns] = d + 1;
			q.push(ns);
		}
	}

	cout << m[goal] << endl;
}