# A*B
def mat_mul(A, B, mod):
    C = [[0]*len(B[0]) for i in range(len(A))]
    for i in range(len(A)):
        for j in range(len(B[0])):
            temp = 0
            for k in range(len(A[0])):
                temp = (temp + A[i][k]*B[k][j])%mod
            C[i][j] = temp
    return C

#A**n
def mat_pow(A, n, mod):
    B = [[0]*len(A) for i in range(len(A))]
    for i in range(len(A)):
        B[i][i] = 1
    for i in range(n.bit_length()):
        if (n >> i)&1:
            B = mat_mul(A, B, mod)
        A = mat_mul(A, A, mod)
    return B

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 = mat_pow(A, t, mod)
    print(A[0][0]%mod)

if __name__ == '__main__':
    main()