UVALIVE 3401 Colored Cubes

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <stack>
#include <queue>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <climits>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <algorithm>
#define LL long long
#define PI 3.1415926535897932626
using namespace std;
int gcd(int a, int b) {return a % b == 0 ? b : gcd(b, a % b);}
int dice24[24][10] = {{2,1,5,0,4,3}, {2,0,1,4,5,3},{2,4,0,5,1,3},{2,5,4,1,0,3},
{4,2,5,0,3,1},{5,2,1,4,3,0},{1,2,0,5,3,4},{0,2,4,1,3,5},{0,1,2,3,4,5},{4,0,2,3,5,1},
{5,4,2,3,1,0},{1,5,2,3,0,4},{5,1,3,2,4,0},{1,0,3,2,5,4},{0,4,3,2,1,5},{4,5,3,2,0,1},
{1,3,5,0,2,4},{0,3,1,4,2,5},{4,3,0,5,2,1},{5,3,4,1,2,0},{3,4,5,0,1,2},{3,5,1,4,0,2},
{3,1,0,5,4,2},{3,0,4,1,5,2}};
const int MAXN = 4;
int N,dice[10][6],ans;
vector<string>names;
int r[MAXN + 10],color[MAXN + 10][6];
int id(const char * name)
{
        string s(name);
        int n = names.size();
        for (int i = 0 ; i < (int) n ;i++)
                if (s == names[i]) return i;
        names.push_back(s);
        return n;
}
void check()
{
        for (int i = 0 ; i < N; i++)
                for (int j = 0 ; j < 6; j++)  color[i][dice24[r[i]][j]] = dice[i][j];
        int tot = 0;
        for (int j = 0 ; j < 6; j++)
        {
                int cnt[24];
                memset(cnt,0,sizeof(cnt));
                int tmp = 0;
                for (int i = 0; i < N ; i++)
                        tmp = max(tmp,++cnt[color[i][j]]);
                tot += N - tmp;
        }
        ans = min(ans,tot);
}
void dfs(int depth)
{
        if (depth == N)check();
        else
        {
                for (int i = 0 ; i <24; i++)
                {
                        r[depth] = i;
                        dfs(depth + 1);
                }
        }
}
int main()
{
        //freopen("sample.txt","r",stdin);
        while (scanf("%d",&N) != EOF)
        {
                if (N == 0) break;
                names.clear();
                for (int i = 0 ; i < N; i++)
                     for (int j = 0 ; j < 6; j++)
                     {
                             char tmp[30];
                             scanf("%s",tmp);
                             dice[i][j] = id(tmp);
                     }
                ans = N * 6;
                r[0] = 0;
                dfs(1);
                printf("%d\n",ans);
        }
        return 0;
}