def cmb(n, r, mod): if ( r<0 or r>n ): return 0 r = min(r, n-r) return g1[n] * g2[r] * g2[n-r] % mod mod = 998244353 N = 2*10**5 g1 = [1]*(N+1) g2 = [1]*(N+1) inverse = [1]*(N+1) for i in range( 2, N + 1 ): g1[i]=( ( g1[i-1] * i ) % mod ) inverse[i]=( ( -inverse[mod % i] * (mod//i) ) % mod ) g2[i]=( (g2[i-1] * inverse[i]) % mod ) inverse[0]=0 N,M = map(int,input().split()) P = list(map(int,input().split())) assert(2<=N<=5000) assert(2<=M<=N) assert(len(P)==N) assert(all(i+1!=P[i] for i in range(N))) P = [P[i]-1 for i in range(N)] cycle = [] used = [False]*N for i in range(N): if not used[i]: used[i] = True c = 1 pos = i while not used[P[pos]]: pos = P[pos] used[pos] = True c += 1 cycle.append(c) P.sort() assert(all(i==P[i] for i in range(N))) n = len(cycle) binom_poly = [1] for i in range(n): c = [cmb(cycle[i],j,mod)*pow(-1,j,mod) for j in range(1,cycle[i]+1)] c[0] = (c[0] + 1) % mod merged = [0 for i in range(len(binom_poly) + len(c) - 1)] for i in range(len(binom_poly)): for j in range(len(c)): merged[i+j] += binom_poly[i] * c[j] merged[i+j] %= mod binom_poly = merged Stirling = [[int(i==j or i==1) for i in range(M+1)] for j in range(N+1)] Stirling[0][0] = 0 for j in range(2,M+1): for i in range(j+1,N+1): Stirling[i][j] = Stirling[i-1][j-1] + j * Stirling[i-1][j] Stirling[i][j] %= mod ans = 0 for i in range(N-n+1): ans += Stirling[n+i][M] * binom_poly[i] ans %= mod ans *= (-1)**N ans %= mod print(ans)