10月21日晚做的OA，内推哒。附代码，自己测试过的，求，求onsite。第一题：email题。
import java.util.*;
public class Solution {
public static void main(String args[]) {
System.out.println("Hello World");
String[] email = { "a@example.com",
"a.b@example.com",
"dupli......cate@example.com",
"d.u.p.l.i.c.a.t.e@example.com",
"d.u.p.l.i.c.a.t.e+[eeeeeee@example.com](mailto:eeeeeee@example.com)"};
int res = emailAdress(email);
System.out.println(res);
}
public static int emailAdress(String[] email) {
if (email == null || email.length == 0) return 0;
int res = 0;
// count is for counting the # of same email address.
HashMap<String, Integer> count = new HashMap<>();
for (String e : email) {
String temp = helper(e);
count.put(temp, count.getOrDefault(temp, 0) + 1);
}
for (int cnt : count.values()) {
if (cnt > 1) res++;
}
for (String s : count.keySet()) {
System.out.println(s);
}
return res;
}
// email = local@domain
// helper method is for 1.local:delete dots(''.'') between some characters
// 2.local:delete ''+'' and all the things after ''+''
private static String helper(String s) {
String ans = "";
int i = 0;
while (i < s.length()) {
if (i == 0) {
ans += s.charAt(i++);
} else if (s.charAt(i) == ''@'') {
ans += s.substring(i);
break;
} else if (s.charAt(i) == ''+'') {
while (s.charAt(i) != ''@'') {
i++;
}
} else if (s.charAt(i) != ''.'') {
ans += s.charAt(i++);
} else {
i++;
}
}
System.out.println(ans);
return ans;
}
}
第二题.蠡口907/159，其实是一道题。
class Solution {
public int totalFruit(int[] tree) {
// count is for storing the current slidewindow,
// how many kinds of trees and the # of it in the slidewindow.
HashMap<Integer, Integer> count = new HashMap<>();
int i = 0, res = 0;
for (int j = 0; j < tree.length; j++) {
count.put(tree[j], count.getOrDefault(tree[j], 0) + 1);
while (count.size() > 2) {
count.put(tree, count.get(tree) - 1);
if (count.get(tree) == 0) count.remove(tree);
i++;
}
res = Math.max(res, j - i + 1);
}
return res;
}
}