def mat_dot(A, B, MOD=pow(10,9)+7):
  #A:n*m行列, B:m*l行列
  n, m, l = len(A), len(A[0]), len(B[0])
  X = [[0]*l for i in range(n)]
  for i in range(n):
    for j in range(l):
      temp = 0
      for k in range(m):
        temp = (temp|(A[i][k]&B[k][j])) % MOD
      X[i][j] = temp
  return X
 
def mat_pow(A, x, MOD=pow(10,9)+7):
  #A^x
  n = len(A)
  X = [[0] * n for i in range(n)]
  for i in range(n):
    X[i][i] = 1
  for i in range(x.bit_length()):
    if (x>>i)&1:
      X = mat_dot(X, A, MOD)
    A = mat_dot(A, A, MOD)
  return X

N,M,T = map(int,input().split())
A = [[0]*N for _ in range(N)] 
for i in range(M):
    a,b = map(int,input().split())
    A[b][a] = 1
#print(A)
AT = mat_pow(A,T)
I = [[0] for _ in range(N)]
#print(I)
I[0][0] = 1
#print(AT)
ANS = mat_dot(AT,I)
#print(ANS)
ret = 0
for x in ANS:
    for y in x:
        ret += y
print(ret)