hdoj 5198 Strange Class 水题

//qscqesze
#include <cstdio>
#include <cmath>
#include <cstring>
#include <ctime>
#include <iostream>
#include <algorithm>
#include <set>
#include <vector>
#include <sstream>
#include <queue>
#include <typeinfo>
#include <fstream>
#include <map>
typedef long long ll;
using namespace std;
//freopen("D.in","r",stdin);
//freopen("D.out","w",stdout);
#define sspeed ios_base::sync_with_stdio(0);cin.tie(0)
#define maxn 200001
#define mod 10007
#define eps 1e-9
//const int inf=0x7fffffff;   //无限大
const int inf=0x3f3f3f3f;
/*
inline ll read()
{
    int x=0,f=1;char ch=getchar();
    while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
    while(ch>=‘0‘&&ch<=‘9‘){x=x*10+ch-‘0‘;ch=getchar();}
    return x*f;
}
int buf[10];
inline void write(int i) {
  int p = 0;if(i == 0) p++;
  else while(i) {buf[p++] = i % 10;i /= 10;}
  for(int j = p-1; j >=0; j--) putchar(‘0‘ + buf[j]);
  printf("\n");
}
*/
//**************************************************************************************

int main()
{
    string s;
    while(cin>>s)
    {
        int flag=1;
        if(s.size()%3!=0)
            flag=0;
        char ch1=s[0];
        for(int i=0;i<s.size()/3;i++)
            if(s[i]!=ch1)
                flag=0;
        char ch2=s[s.size()/3];
        for(int i=s.size()/3;i<s.size()/3*2;i++)
            if(s[i]!=ch2)
                flag=0;
        char ch3=s[s.size()/3*2];
        for(int i=s.size()/3*2;i<s.size();i++)
            if(s[i]!=ch3)
                flag=0;
        if(ch1==ch2||ch2==ch3||ch1==ch3)
            flag=0;
        if(flag)
            cout<<"YES"<<endl;
        else
            cout<<"NO"<<endl;
    }
}