#include using namespace std; typedef signed long long ll; #undef _P #define _P(...) (void)printf(__VA_ARGS__) #define FOR(x,to) for(x=0;x<(to);x++) #define FORR(x,arr) for(auto& x:arr) #define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++) #define ALL(a) (a.begin()),(a.end()) #define ZERO(a) memset(a,0,sizeof(a)) #define MINUS(a) memset(a,0xff,sizeof(a)) //------------------------------------------------------- int N; string S[202]; ll dp[1<<20]; ll mo=1000000007; ll fact[21]; ll ret[21]; int cost[20][20]; void solve() { int i,j,k,l,r,x,y; string s; cin>>N; FOR(i,N) cin>>S[i]; FOR(x,N) FOR(y,N) { cost[x][y]=1; while(cost[x][y]<=S[x].size() && cost[x][y]<=S[y].size() && S[x][cost[x][y]-1]==S[y][cost[x][y]-1]) cost[x][y]++; } fact[0]=1; FOR(i,N) fact[i+1]=fact[i]*(i+1)%mo; for(int mask=0;mask<1<