mod = 998244353

def mat_mul(a, b):
    n_a, m_a = len(a), len(a[0])
    n_b, m_b = len(b), len(b[0])
    res = [[0] * m_b for i in range(n_a)]
    for i in range(n_a):
        for k in range(m_a):
            for j in range(m_b):
                res[i][j] += a[i][k] * b[k][j]
                res[i][j] %= mod
    return res

def mat_pow(a, k):
    if k == 1: return a
    n = len(a)
    res = [[0] * n for i in range(n)]
    for i in range(n):
        res[i][i] = 1
    while k:
        if k & 1:
            res = mat_mul(res, a)
        a = mat_mul(a, a)
        k >>= 1
    return res

n, m, t = map(int, input().split())
G = [[0] * n for i in range(n)]
for _ in range(m):
	a, b = map(int, input().split())
	G[a][b] = 1
	G[b][a] = 1
G = mat_pow(G, t)
b = [[0] * n for i in range(n)]
b[0][0] = 1
G = mat_mul(G, b)
print(G[0][0])