N = 2*10**5
mod = 998244353
g1 = [1]*(N+1) # 元テーブル
g2 = [1]*(N+1) #逆元テーブル
inverse = [1]*(N+1) #逆元テーブル計算用テーブル

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

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

def fwt(n,A):
    assert len(A) == 2**n
    for i in range(n):
        t = 2**i
        for j in range(2**n):
            if j&t==0:
                A[j] += A[j|t]
    return A

def ifwt(n,A):
    assert len(A) == 2**n
    for i in range(n):
        t = 2**i
        for j in range(2**n):
            if j&t==0:
                A[j] -= A[j|t]
    return A

inv = pow(1024,mod-2,mod)
 
def _fourier(f, inverse = False):
    f = f[:]
    n = (len(f) - 1).bit_length()
    for d in range(n):
        for U in range(1 << n):
            if not U >> d & 1:
                s, t = f[U], f[U | 1 << d]
                f[U], f[U | 1 << d] = (s + t)%mod, (s - t)%mod
    if inverse:
        f = [v *inv % mod for v in f]
    return f
 
def convolution(f, g):
    return _fourier([a * b  % mod for a, b in zip(_fourier(f), _fourier(g))], inverse = 1)

import sys,random,bisect
from collections import deque,defaultdict
from heapq import heapify,heappop,heappush
from itertools import permutations
from math import log,gcd

input = lambda :sys.stdin.readline()
mi = lambda :map(int,input().split())
li = lambda :list(mi())

def mat_mul(X,Y):
    n,m = len(X),len(Y[0])
    res = [[0 for j in range(m)] for i in range(n)]
    for i in range(n):
        for j in range(m):
            for k in range(len(Y)):
                res[i][j] += X[i][k] * Y[k][j]
                res[i][j] %= mod
    return res

N,M,T = mi()
A = [[0 for j in range(N)] for i in range(N)]
for i in range(M):
    s,t = mi()
    A[s][t] = A[t][s] = 1

E = [[int(i==j) for j in range(N)] for i in range(N)]

while T:
    if T&1:
        E = mat_mul(A,E)
    A = mat_mul(A,A)
    T >>= 1

ans = E[0][0]
print(ans)