#include <cstdio>
#include <vector>
#include <cstring>
#include <algorithm>
#include <climits>
using namespace std;

#define MAXN 110
#define MAXL 30

char a0[] = "QWERTYUIOP";
int L1 = sizeof(a0)-1;
char a1[] = "ASDFGHJKL";
int L2 = sizeof(a1)-1;
char a2[] = "ZXCVBNM";
int L3 = sizeof(a2)-1;

int dst[MAXL][MAXL];

int cabs(int x) {
	return (x < 0) ? (-x) : x;
}

void precompute() {
	memset(dst, 0, sizeof(dst));
	for (int i = 0; i < L1; ++i)
	for (int j = i + 1; j < L1; ++j)
		dst[a0[i] - 'A'][a0[j] - 'A'] = dst[a0[j] - 'A'][a0[i] - 'A'] = cabs(i - j);
	for (int i = 0; i < L2; ++i)
	for (int j = i + 1; j < L2; ++j)
		dst[a1[i] - 'A'][a1[j] - 'A'] = dst[a1[j] - 'A'][a1[i] - 'A'] = cabs(i - j);
	for (int i = 0; i < L3; ++i)
	for (int j = i + 1; j < L3; ++j)
		dst[a2[i] - 'A'][a2[j] - 'A'] = dst[a2[j] - 'A'][a2[i] - 'A'] = cabs(i - j);

	for (int i = 0; i < L1; ++i)
	for (int j = 0; j < L2; ++j)
		dst[a0[i] - 'A'][a1[j] - 'A'] = dst[a1[j] - 'A'][a0[i] - 'A'] = cabs(i - j) + 1;
	for (int i = 0; i < L2; ++i)
	for (int j = 0; j < L3; ++j)
		dst[a1[i] - 'A'][a2[j] - 'A'] = dst[a2[j] - 'A'][a1[i] - 'A'] = cabs(i - j) + 1;
	for (int i = 0; i < L1; ++i)
	for (int j = 0; j < L3; ++j)
		dst[a0[i] - 'A'][a2[j] - 'A'] = dst[a2[j] - 'A'][a0[i] - 'A'] = cabs(i - j) + 2;
}

int dp[MAXN][MAXL];

int solve(char *buf) {
	int L = strlen(buf);
	int A = L1 + L2 + L3;
	for (int a = 0; a < A; ++a) {
		int l1 = buf[0] - 'A';
		int l2 = a;
		dp[0][l2] = min(dst['F' - 'A'][l1] + dst['J' - 'A'][l2], dst['F' - 'A'][l2] + dst['J' - 'A'][l1]);
	}
	for (int i = 1; i < L; ++i)
	for (int a = 0; a < A; ++a) {
		dp[i][a] = INT_MAX;
		for (int b = 0; b < A; ++b) {
			int l1 = buf[i] - 'A';
			dp[i][a] = min(dp[i][a],
				dp[i - 1][b] + min(dst[b][l1] + dst[buf[i - 1] - 'A'][a], dst[b][a] + dst[buf[i - 1] - 'A'][l1]));
		}
	}
	int answer = INT_MAX;
	for (int i = 0; i < A; ++i)
		answer = min(answer, dp[L - 1][i]);
	return answer;
}

char buff[100];

int main() {
	precompute();
	scanf("%s", buff);
	printf("%d\n", solve(buff));
	return 0;
}