CF236A Boy or Girl（找字符数，可以考虑去重）

题目描述

Those days, many boys use beautiful girls' photos as avatars in forums. So it is pretty hard to tell the gender of a user at the first glance. Last year, our hero went to a forum and had a nice chat with a beauty (he thought so). After that they talked very often and eventually they became a couple in the network.

But yesterday, he came to see "her" in the real world and found out "she" is actually a very strong man! Our hero is very sad and he is too tired to love again now. So he came up with a way to recognize users' genders by their user names.

This is his method: if the number of distinct characters in one's user name is odd, then he is a male, otherwise she is a female. You are given the string that denotes the user name, please help our hero to determine the gender of this user by his method.

输入格式

The first line contains a non-empty string, that contains only lowercase English letters — the user name. This string contains at most 100 letters.

输出格式

If it is a female by our hero's method, print "CHAT WITH HER!" (without the quotes), otherwise, print "IGNORE HIM!" (without the quotes).

题意翻译

那些日子，许多男孩在论坛上使用漂亮女孩的照片作为化身。所以很难在第一眼就知道用户的性别。去年，我们的英雄去了一个论坛，和一位美女聊天（他想是这样）。之后，他们经常交谈，最终他们成为了网络中的一对情侣。

但是昨天，他在现实世界里看到了“她”，发现“她”其实是一个非常强壮的男人！我们的英雄很伤心，他太累了，不能再爱了。因此，他想出了一种通过用户名来识别用户性别的方法。

这是他的方法：如果用户名中的不同字符数是奇数，那么他是男性，否则她是女性。您给出了表示用户名的字符串，请用我们的方法帮助我们的英雄确定这个用户的性别。

如果是女生，输出 CHAT WITH HER!；如果是男生，则输出IGNORE HIM!。

输入输出样例

输入

wjmzbmr

输出  

CHAT WITH HER!

输入

xiaodao

输出

IGNORE HIM!

输入  

sevenkplus

输出  

CHAT WITH HER!

首先我们分析我们可以遍历一遍，然后我们统计每个字符的数目，然后我们再遍历一遍只要出现有字符大于0的我们就加1；最后判断这个加的数是不是奇数或者偶数，就行了，

还有一种方法就是去重函数，首先我们先拍好序，然后我们再用erase和unique函数解决，具体操作看代码；

一般代码；

#include <bits/stdc++.h>
using namespace std;
int a[37],ans;
int main()
{
  char s;
  while (cin >> s)
    {
      a[s-96]++;
    }
  for (int i = 1; i <= 26; i++)
    {
      if (a[i] != 0) ans++;
      } 
  if (ans % 2 == 0) cout << "CHAT WITH HER!";
    else cout << "IGNORE HIM!"; 
 } 

去重代码

#include<bits/stdc++.h>
using namespace std;
string s;
int main(){
  cin>>s;
  sort(s.begin(),s.end());
  s.erase(unique(s.begin(),s.end()),s.end());
  puts(s.size()&1?"IGNORE HIM!":"CHAT WITH HER!");
}