import sys
input = sys.stdin.buffer.readline

# 行列の乗算(mod)
def mat_mul(a, b, mod):
	I, K, J = len(a), len(b), len(b[0])
	c = [[0 for j in range(J)] for i in range(I)]
	for i in range(I):
		for k in range(K):
			for j in range(J):
				c[i][j] += a[i][k] * b[k][j]
				c[i][j] %= mod
	return c

# 行列の累乗(mod)
def mat_pow(a, n, mod):
	b = [[0 for j in range(len(a))] for i in range(len(a))]
	for i in range(len(a)):
		b[i][i] = 1
	while n > 0:
		if n & 1:
			b = mat_mul(b, a, mod)
		a = mat_mul(a, a, mod)
		n >>= 1
	return b

N, M, T = map(int, input().split())
G = [[0 for j in range(N)] for i in range(N)]
mod = 998244353
for i in range(M):
	s, t = map(int, input().split())
	G[s][t] = 1
	G[t][s] = 1

ans = mat_pow(G, T, mod)
print(ans[0][0])