from collections import *
from itertools import *
from functools import *
from heapq import *
import sys,math
input = sys.stdin.readline
# sys.setrecursionlimit(10**6)

N,K = map(int,input().split())
e = [[] for _ in range(N)]
for _ in range(N):
  u,v = map(int,input().split())
  u -= 1
  v -= 1
  e[u].append(v)
  e[v].append(u)
def namori_decomposition(e):
    
    
    ## cycle,root
    ## root : その頂点が属するcycle上の点を返す
    
    
    n = len(e)
    deg = [len(e[i]) for i in range(n)]
    v = deque()
    for i in range(n):
        if deg[i]==1:
            v.append(i)
            
    cycle = [True]*n
    while v:
        x = v.popleft()
        cycle[x]=False
        for ix in e[x]:
            deg[ix] -= 1
            if deg[ix] == 1:
                v.append(ix)
                
    
    E = [[] for _ in range(n)]
    for i in range(n):
        for j in e[i]:
            if cycle[i]&cycle[j]:
                continue
            E[i].append(j)
            E[j].append(i)
                
    root = [-1]*n
    for i in range(n):
        if cycle[i]:
            v.append(i)
            root[i] = i
            while v:
                x = v.popleft()
                for ix in E[x]:
                    if root[ix]==-1:
                        root[ix] = i
                        v.append(ix)
    return cycle,root

cycle,root = namori_decomposition(e)

n = sum(cycle)
mod = 998244353
C = Counter(root)
ans = (K-1)*(pow(K-1,n-1,mod) - pow(-1,n-1,mod))%mod
#956138134
for v in C.values():
  
  ans *= pow(K-1,v-1,mod)
  ans %= mod
print(ans)