http://poj.org/problem?id=3349
#include<iostream>
#include<cstdio>
#include<string.h>
#include<algorithm>
#include<queue>
#include<vector>
#include<math.h>
#define N 5000
using namespace std;
struct node
{
int a[6];
int sum;
}mem[100005];
vector< int >str[5000];
inline bool find(int l,int k)
{
int j;
for(int i=0;i<str[k].size();++i)
{ j=str[k][i];
if(j!=l)
{
int b;
for(b=0;b<6;++b)
{
if(mem[l].a[0]==mem[j].a[b]&&mem[l].a[1]==mem[j].a[(b+1)%6]&&mem[l].a[2]==mem[j].a[(b+2)%6]&&mem[l].a[3]==mem[j].a[(b+3)%6]&&
mem[l].a[4]==mem[j].a[(b+4)%6]&&mem[l].a[5]==mem[j].a[(b+5)%6])
return true;
if(mem[l].a[5]==mem[j].a[b]&&mem[l].a[4]==mem[j].a[(b+1)%6]&&mem[l].a[3]==mem[j].a[(b+2)%6]&&mem[l].a[2]==mem[j].a[(b+3)%6]
&& mem[l].a[1]==mem[j].a[(b+4)%6]&&mem[l].a[0]==mem[j].a[(b+5)%6])
return true;
}
}
}
return false;
}
int main()
{
//freopen("data.txt","r",stdin);
//freopen("A-large-practice.out","w",stdout);
int n;
int i;
int l;
while(scanf("%d",&n)!=EOF)
{
for(l=0;l<n;++l)
{
mem[l].sum=0;
for(i=0;i<6;++i)
{
scanf("%d",&mem[l].a[i]);
mem[l].sum+=mem[l].a[i];
//cout<<mem[l].sum<<endl;
}
//cout<<l<<" "<<mem[l].sum%N<<endl;
str[mem[l].sum%N].push_back(l);
}
for(l=0;l<n;++l)
{
if(find(l,mem[l].sum%N))
break;
}
if(l<n)
{
printf("Twin snowflakes found.\n");
}
else
{
printf("No two snowflakes are alike.\n");
}
}
return 0;
}
