mod = 998244353
n,m,t = map(int,input().split())
G = [[0]*n for _ in range(n)]
for _ in range(m):
    u,v = map(int,input().split())
    G[u][v] = G[v][u] = 1
def f(A,B):
    C = [[0]*n for _ in range(n)]
    for i in range(n):
        for j in range(n):
            for k in range(n):
                C[i][j] += A[i][k]*B[k][j]%mod
                C[i][j] %= mod
    return C
def g(n):
    if n == 1:
        return G
    if n%2:
        return f(G,g(n-1))
    T = g(n//2)
    return f(T,T)
ans = g(t)[0][0]
print(ans)