package google;

import com.sun.tools.javac.util.StringUtils;

import java.util.HashMap;

import java.util.Map;

public class DistinctMails {

public int numUniqueEmails(String[] emails) {

Map<String, Integer> emap = new HashMap<>();

for (String email : emails) {

String key = getEmail(email);

if (!emap.containsKey(key)) {

emap.put(key, 1);

}

}

return emap.keySet().size();

}

private String getEmail(String original) {

StringBuffer stringBuffer = new StringBuffer();

boolean skip = false;

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

if (original.charAt(i) == '@') {

return formDomain(stringBuffer, original, i);

} else if (original.charAt(i) == '+') {

skip = true;

} else if (original.charAt(i) != '.' && skip == false) {

stringBuffer.append(original.charAt(i));

}

}

return "";

}

private String formDomain(StringBuffer buffer, String original, int i) {

for (; i < original.length(); i++) {

buffer.append(original.charAt(i));

}

return buffer.toString();

}

}