MOD = 998244353
N,M,T = map(int,input().split())
G = {i:[] for i in range(N)}
for _ in range(M):
    s,t = map(int,input().split())
    G[s].append(t)
    G[t].append(s)
A = [[0 for _ in range(N)] for _ in range(N)]
for i in range(N):
    for j in G[i]:
        A[i][j] = 1
def matmul(A,B):
    C = [[0 for _ in range(N)] for _ in range(N)]
    for i in range(N):
        for j in range(N):
            for k in range(N):
                C[i][j] += A[i][k]*B[k][j]
                C[i][j] %= MOD
    return C
def matpow(A,k):
    if k==0:
        return [[1 if i==j else 0 for j in range(N)] for i in range(N)]
    if k==1:
        return A
    if k%2==0:
        B = matpow(A,k//2)
        return matmul(B,B)
    else:
        B = matpow(A,k//2)
        return matmul(matmul(B,B),A)
B = matpow(A,T)
u = [0 for _ in range(N)]
u[0] = 1
v = [0 for _ in range(N)]
for i in range(N):
    for j in range(N):
        v[i] += B[i][j]*u[j]
        v[i] %= MOD
print(v[0])