import sys
input = sys.stdin.readline
N, M, T = map(int, input().split())

bn = list(map(int, bin(T)[2: ]))
ln = len(bn)

d = [[[0] * N for _ in range(N)] for _ in range(ln)]
for _ in range(M):
  u, v = map(int, input().split())
  d[0][u][v] = 1

for t in range(ln - 1):
  for k in range(N):
    for i in range(N):
      for j in range(N):
        d[t + 1][i][j] |= d[t][i][k] & d[t][k][j]

dt = [[0] * N for _ in range(N)]
dt[0][0] = 1
for tt in range(ln):
  t = ln - tt - 1
  if bn[tt] == 0: continue
  tdt = [[0] * N for _ in range(N)]
  for k in range(N):
    for i in range(N):
      for j in range(N):
        tdt[i][j] |= dt[i][k] & d[t][k][j]
  dt = tdt

print(sum(dt[0]))