import sys input = lambda : sys.stdin.readline().rstrip() sys.setrecursionlimit(2*10**5+10) write = lambda x: sys.stdout.write(x+"\n") n,m = list(map(int, input().split())) p = list(map(lambda x: int(x)-1, input().split())) M = 998244353 N = n+m+100 # 必要なテーブルサイズ g1 = [0] * (N+1) # 元テーブル g2 = [0] * (N+1) #逆元テーブル inverse = [0] * (N+1) #逆元テーブル計算用テーブル g1[0] = g1[1] = g2[0] = g2[1] = 1 inverse[0], inverse[1] = [0, 1] for i in range( 2, N + 1 ): g1[i] = ( g1[i-1] * i ) % M inverse[i] = ( -inverse[M % i] * (M//i) ) % M # ai+b==0 mod M <=> i==-b*a^(-1) <=> i^(-1)==-b^(-1)*aより g2[i] = (g2[i-1] * inverse[i]) % M def cmb(n, r, M): if ( r<0 or r>n ): return 0 r = min(r, n-r) return ((g1[n] * g2[r] % M) * g2[n-r]) % M def perm(n, r, M): if (r<0 or r>n): return 0 return (g1[n] * g2[n-r]) % M def part(p): n = len(p) done = [0]*n ans = [] for i in range(n): if done[i]: continue l = [i] i0 = i done[i] = 1 while p[i]!=i0: i = p[i] l.append(i) done[i] = 1 ans.append(l) return ans d = {} def sub(i,j): if (i,j) in d: return d[i,j] dp0 = dp1 = 0 dp0 = j for ii in range(i-1): dp0, dp1 = dp1, dp1*(j-2) + dp0*(j-1) dp0 %= M dp1 %= M ans = dp1 if i==1: ans = j d[i,j] = ans return ans l = part(p) nums = [len(item) for item in l] ans = 0 for i in range(m): s = 1 if i%2==0 else -1 val = s for num in nums: val *= sub(num, m-i) val %= M ans += val * cmb(m, i, M) # ans += val * pow(m-i, len(l), M) # print(i,val%M,s) ans *= g2[m] print(ans%M)