import numpy as np


def matqpow2(base: "np.ndarray", exp: int, mod: int) -> "np.ndarray":
    """np矩阵快速幂"""
    res = np.eye(*base.shape, dtype=np.uint64)
    while exp:
        if exp & 1:
            res = (res @ base) % mod
        base = (base @ base) % mod
        exp >>= 1
    return res


n, m, k = map(int, input().split())
adjMatrix = [[0] * n for _ in range(n)]
for _ in range(m):
    u, v = map(int, input().split())
    u, v = u - 1, v - 1
    adjMatrix[u][v] = adjMatrix[v][u] = 1

adjMatrix = np.array(adjMatrix, dtype=np.uint64)
T = matqpow2(adjMatrix, k, 998244353)
print(T[0][0])