def dot(A1,A2,n,mod):
  # n:行列のサイズ
  A = [[0]*n for _ in range(n)]
  for i in range(n):
    for j in range(n):
      for k in range(n):
        A[i][j] += A1[i][k]*A2[k][j]
        A[i][j] %= mod
  return A

def pow_mat(A,k,n,mod):
  # A:累乗する行列, k:累乗数, n:行列Aのサイズ
  P = [[0]*n for _ in range(n)]
  for i in range(n): P[i][i] = 1
  while k:
    if k&1: P = dot(P,A,n,mod)
    A = dot(A,A,n,mod)
    k >>= 1
  return P

n,m,T = map(int,input().split())
st = [[] for i in range(n)]
mod = 998244353

st = [[0]*n for i in range(n)]

for i in range(m):
    s,t = map(int,input().split())
    st[s][t] = 1
    st[t][s] = 1

A = pow_mat(st,T,n,mod)
 
print(A[0][0])