题目
代码部分一(96ms 26.74%)
class Solution {
public int numUniqueEmails(String[] emails) {
Set<String> set = new HashSet<>();
int res = 0;
String[] str = new String[2];
int len = emails.length;
for(int i = 0; i < len; i++){
str = emails[i].split("@");
String temp = str[0].replaceAll("\\.", "");
int end = temp.indexOf("+");
if(end != -1) str[0] = temp.substring(0, end);
if(!set.contains(str[0]+ "@" +str[1])){
res++;
set.add(str[0] + "@" + str[1]);
}
}
return res;
}
}
代码部分二(75ms 47.21%)
class Solution {
public int numUniqueEmails(String[] emails) {
Set<String> set = new HashSet<>();
int res = 0;
String[] str = new String[2];
int len = emails.length;
for(int i = 0; i < len; i++){
str = emails[i].split("@");
String temp = "";
int end = str[0].indexOf("+");
if(end != -1) temp = str[0].substring(0, end);
else temp = str[0];
str[0] = "";
char[] ch = temp.toCharArray();
for(int j = 0; j < ch.length; j++){
if(ch[j] != '.') str[0] += ch[j];
}
if(!set.contains(str[0]+ "@" +str[1])){
res++;
set.add(str[0] + "@" + str[1]);
}
}
return res;
}
}
代码部分三(27ms 85.27%)
class Solution {
public int numUniqueEmails(String[] emails) {
Set<String> set = new HashSet<>();
String last = "";
String first = "";
for(String email : emails) {
last = email.substring(email.indexOf("@"));
first = email.substring(0,email.indexOf("@"));
char [] arr = new char[first.length()];
arr = first.toCharArray();
int j = 0;
char [] arr1 = new char[100];
for(int i = 0; i < arr.length; i++) {
if(arr[i] == '.') {
continue;
}
if(arr[i] == '+') {
break;
}
arr1[j] = arr[i];
j++;
}
set.add(first.valueOf(arr1).trim()+last);
}
return set.size();
}
}
代码部分四(9ms 100%)
class Solution {
public int numUniqueEmails(String[] emails) {
Set<String> set = new HashSet<>();
for(String str : emails){
int n = str.indexOf('@');
String temp = str.substring(n);
set.add(temp);
}
return set.size();
}
}