LC_1320.java

class Solution {
     public int minimumDistance(String word) {
        int dp[] = new int[26], res = 0, save = 0, n = word.length();
        for (int i = 0; i < n - 1; ++i) {
            int b = word.charAt(i) - 'A', c = word.charAt(i + 1) - 'A';
            for (int a = 0; a < 26; ++a)
                dp[b] = Math.max(dp[b], dp[a] + d(b, c) - d(a, c));
            save = Math.max(save, dp[b]);
            res += d(b, c);
        }
        return res - save;

    }

    private int d(int a, int b) {
        return Math.abs(a / 6 - b / 6) + Math.abs(a % 6 - b % 6);
    }
}