#include <algorithm>
int map[30][30];
int chk[30];
inline long long mapping(int num)
{
if(num <= 0) return 1;
bool color[5];
register int i;
long long ans = 0;
for(i=1;i<=4;i++) color[i] = false;
for(i=1;i<=map[num][0];i++)
{
if(map[num][i] <= num) break;
color[chk[map[num][i]]] = true;
}
if(map[num][0] == 0) ans += 4 * mapping(num-1);
else for(i=1;i<=4;i++)
{
if(!color[i])
{
chk[num] = i;
ans += mapping(num-1);
chk[num] = 0;
}
}
return ans;
}
bool cmp(int aa, int bb){return aa > bb;}
long long NumberOfMaps (int N, int M, int *A, int *B){
int i;
for(i=0;i<M;i++)
{
map[A[i]][++map[A[i]][0]] = B[i];
map[B[i]][++map[B[i]][0]] = A[i];
}
for(i=1;i<=N;i++) std::sort(map[i]+1,map[i]+(map[i][0]+1),cmp);
return mapping(N);
}
