class Solution {
    public int numberOfSpecialChars(String word) {
        int n = word.length();
        int[] cnt = new int[26];
        for (int i = 0; i < n; i++) {
            int o = word.charAt(i) - 'A';
            if (o > 26) {
                cnt[o - 32] |= 2;
            } else {
                cnt[o] |= 1;
            }
        }
        int ans = 0;
        for (int i = 0; i < 26; i++) {
            if (cnt[i] == 3) {
                ans++;
            }
        }
        return ans;
    }
}