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/*    BZOJ 1019: [SHOI2008]汉诺塔    我是代码的搬运工，啦啦啦    真心不明白QAQ*/#include 
     
      #define rg register#define Max 35typedef long long LL;int g[3][Max], l[Max], q[Max]; LL f[3][Max];int main (int argc, char *argv[]){    int N; char t[5]; scanf ("%d", &N); rg int i, j; int x, y;    for (i = 0; i < 6; ++ i)        scanf ("%s", t), l[i] = t[0] - 'A', q[i] = t[1] - 'A';    f[0][1] = f[1][1] = f[2][1] = 1;    for (i = 0; i < 3; ++ i)        for (j = 0; j < 6; ++ j)            if (l[j] == i) { g[i][1] = q[j]; break; }    for (i = 2; i <= N; ++ i)        for (j = 0; j < 3; ++ j)        {            x = g[j][i - 1], y = 3 - j - x;            if (g[x][i - 1] == y) f[j][i] = f[j][i - 1] + 1 + f[x][i - 1], g[j][i] = y;            else f[j][i] = f[j][i - 1] + 2 + f[x][i - 1] + f[j][i - 1], g[j][i] = x;        }    printf ("%lld", f[0][N]); return 0;}