public String shortestCompletingWord(String licensePlate, String[] words) {

int[] charMap = new int[26];

for (char c: licensePlate.toCharArray()) {

if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {

char lowerC = Character.toLowerCase(c);

charMap[lowerC - 'a'] += 1;

}

}

String res = "";

int len = Integer.MAX_VALUE;

for (String word: words) {

int[] map = new int[26];

for (char c: word.toCharArray()) map[c - 'a'] += 1;

boolean match = true;

for (int i=0; i<26; i++) {

if (map[i] < charMap[i]) {

match = false;

break;

}

}

if (match && word.length() < len) {

res = word;

len = word.length();

}

}

return res;

}

}