private static final int A = 65;

public static int solution(String str1, String str2) {

HashMap<Integer, Integer> s1 = getTokens(str1.toUpperCase());

HashMap<Integer, Integer> s2 = getTokens(str2.toUpperCase());

return (int) (getJaccad(s1, s2) * 65536);

}

private static double getJaccad(HashMap<Integer, Integer> s1, HashMap<Integer, Integer> s2) {

if (s1.isEmpty() && s2.isEmpty())

return 1;

return (double) intersect(s1, s2) / union(s1, s2);

}

private static HashMap<Integer, Integer> getTokens(String s) {

HashMap<Integer, Integer> tokens = new HashMap<>();

for (int i = 0; i < s.length() - 1; i++) {

if (!isAlpha(s.charAt(i)) || !isAlpha(s.charAt(i + 1)))

continue;

tokens.compute(makeToken(s, i), (k, v) -> v == null ? 1 : v + 1);

}

return tokens;

}

private static boolean isAlpha(char c) {

return A <= c && c < A + 26;

}

private static int makeToken(String s, int i) {

return s.charAt(i) * 100 + s.charAt(i + 1);

}

private static int intersect(HashMap<Integer, Integer> s1, HashMap<Integer, Integer> s2) {

int intersection = 0;

for (int key : s1.keySet())

intersection += s2.containsKey(key) ? Math.min(s1.get(key), s2.get(key)) : 0;

return intersection;

}

private static int union(HashMap<Integer, Integer> s1, HashMap<Integer, Integer> s2) {

int union = 0;

for (int key : s1.keySet())

union += s2.containsKey(key) ? Math.max(s1.get(key), s2.get(key)) : s1.get(key);

for (int key : s2.keySet())

union += !s1.containsKey(key) ? s2.get(key) : 0;

return union;

}

public static void main(String args[]) {

String[] s1 = { "french", "shake hands", "AAAA12", "e=m*c^2" };

String[] s2 = { "FRANCE", "handshake", "aa1+aa2", "E=M*C^2", };

for (int i = 0; i < s2.length; i++) {

System.out.println(solution(s1[i], s2[i]));

}

// 16384

// 65536

// 43690

// 65536

}