import numpy as np

#A**n
def mat_pow(A, n, mod):
    size = len(A)
    res = np.eye(size, dtype=np.object)
    while n > 0:
        if n & 1 == 1:
            res = res @ A
            res %= mod
        A = A @ A
        A %= mod
        n = n>>1
    return res

import sys
import io, os
input = io.BytesIO(os.read(0,os.fstat(0).st_size)).readline

mod = 998244353

def main():

    n, m, t = map(int, input().split())
    A = [[0]*n for i in range(n)]
    for i in range(m):
        u, v = map(int, input().split())
        A[u][v] = 1
        A[v][u] = 1
    A = np.array(A)
    A = mat_pow(A, t, mod)
    ans = A[0][0]%mod
    print(ans)

if __name__ == '__main__':
    main()