import sys
readline = sys.stdin.readline

N, K = map(int, readline().split())
mod = 998244353
inf = 10 ** 18
D = [(inf, inf)]
cnt = [0] * 202020
for i in range(N):
    L, R = map(int, readline().split())
    D.append((L, R))
D.sort(reverse=True)
val = 1
size = 0
for i in range(202020):
    size -= cnt[i]
    while D[-1][0] == i:
        _, r = D.pop()
        cnt[r] += 1
        size += 1
        val *= K + 1 - size
        val %= mod
print( (pow(K, N, mod) - val)%mod )