MOD = 998244353
from heapq import *

N, K = map(int, input().split())
LR = [list(map(int, input().split())) for _ in range(N)]
LR.sort()
q = []
cnt = 0
All = pow(K, N, MOD)
tmp = 1
for l, r in LR:
    if q:
        while q and q[0] <= l:
            cnt -= 1
            heappop(q)
    tmp *= (K - cnt)
    tmp %= MOD
    cnt += 1
    heappush(q,r)
print(All - tmp)