#include <bits/stdc++.h>
using namespace std;
int alphabetTimes[] = {1, 2, 3, 1, 2, 3, 1,
2, 3, 1, 2, 3, 1, 2,
3, 1, 2, 3, 4, 1, 2,
3, 1, 2, 3, 4};
int main()
{
string s;
while (cin >> s)
{
int TotalTime = alphabetTimes[s[0] - 'a'];
for (int i = 1; i < s.size(); i++)
{
if (abs(s[i] - s[i - 1]) ==
alphabetTimes[max(s[i], s[i - 1]) - 'a'] -
alphabetTimes[min(s[i], s[i - 1]) - 'a'])
TotalTime += 2;
TotalTime += alphabetTimes[s[i] - 'a'];
}
cout << TotalTime << endl;
}
return 0;
}