//naive, TLE expected #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i)) #define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i)) #define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i)) #if defined(_MSC_VER) || __cplusplus > 199711L #define aut(r,v) auto r = (v) #else #define aut(r,v) __typeof(v) r = (v) #endif #define each(it,o) for(aut(it, (o).begin()); it != (o).end(); ++ it) #define all(o) (o).begin(), (o).end() #define pb(x) push_back(x) #define mp(x,y) make_pair((x),(y)) #define mset(m,v) memset(m,v,sizeof(m)) #define INF 0x3f3f3f3f #define INFL 0x3f3f3f3f3f3f3f3fLL using namespace std; typedef vector vi; typedef pair pii; typedef vector > vpii; typedef long long ll; template inline void amin(T &x, U y) { if(y < x) x = y; } template inline void amax(T &x, U y) { if(x < y) x = y; } struct FenwickTree { typedef int T; vector v; void init(int n) { v.assign(n, 0); } void add(int i, T x) { for(; i < (int)v.size(); i |= i+1) v[i] += x; } T sum(int i) const { //[0, i) T r = 0; for(-- i; i >= 0; i = (i & (i+1)) - 1) r += v[i]; return r; } T sum(int left, int right) const { //[left, right) return sum(right) - sum(left); } }; template struct ModInt { static const int Mod = MOD; unsigned x; ModInt(): x(0) { } ModInt(signed sig) { int sigt = sig % MOD; if(sigt < 0) sigt += MOD; x = sigt; } ModInt(signed long long sig) { int sigt = sig % MOD; if(sigt < 0) sigt += MOD; x = sigt; } int get() const { return (int)x; } ModInt &operator+=(ModInt that) { if((x += that.x) >= MOD) x -= MOD; return *this; } ModInt &operator-=(ModInt that) { if((x += MOD - that.x) >= MOD) x -= MOD; return *this; } ModInt &operator*=(ModInt that) { x = (unsigned long long)x * that.x % MOD; return *this; } ModInt operator+(ModInt that) const { return ModInt(*this) += that; } ModInt operator-(ModInt that) const { return ModInt(*this) -= that; } ModInt operator*(ModInt that) const { return ModInt(*this) *= that; } }; typedef ModInt<1000000007> mint; int main() { int N; long long K; while(cin >> N >> K) { vi p(N); rep(i, N) scanf("%d", &p[i]), -- p[i]; mint ans; FenwickTree ft; for(ll k = 0; k < K; ++ k) { ft.init(N); ll inv = 0; rep(i, N) { inv += i - ft.sum(p[i]+1); ft.add(p[i], 1); } ans += inv; next_permutation(all(p)); } printf("%d\n", ans.get()); } return 0; }