## https://yukicoder.me/problems/no/1750

MOD = 998244353

def prod_matrix(N, mat1, mat2):
    new_matrix = [[0] * N for _ in range(N)]
    for i in range(N):
        for j in range(N):
            for k in range(N):
                new_matrix[i][j] += (mat1[i][k] * mat2[k][j]) % MOD
                new_matrix[i][j] %= MOD
    return new_matrix

def prod_vector(N, mat, vec):
    new_vector = [0] * N
    for i in range(N):
        for j in range(N):
            new_vector[i] += (mat[i][j] * vec[j]) % MOD
            new_vector[i] %= MOD
    return new_vector


def main():
    N, M, T = map(int, input().split())
    st = []
    for _ in range(M):
        s, t = map(int, input().split())
        st.append((s, t))
    
    base_matrix = [
        [0] * N for _ in range(N)
    ]
    for s, t in st:
        base_matrix[s][t] = 1
        base_matrix[t][s] = 1
    
    vector = [0] * N
    vector[0] = 1

    while T > 0:
        if T % 2 == 1:
            vector = prod_vector(N, base_matrix, vector)
        base_matrix = prod_matrix(N, base_matrix, base_matrix)
        T //= 2
    
    print(vector[0])
    








if __name__ == "__main__":
    main()