local bor, band = bit.bor, bit.band
local ffi = require("ffi")
local C = ffi.C
ffi.cdef[[
long long atoll(const char*);
]]

local function lltonumber(str)
  return C.atoll(str)
end

local n, m, t = io.read():match("(%d+) (%d+) (%d+)")
n = tonumber(n)
m = tonumber(m)
t = lltonumber(t)

local mat = {}
for i = 1, n do
  mat[i] = {}
  for j = 1, n do
    mat[i][j] = 0
  end
end
for i = 1, m do
  local a, b = io.read("*n", "*n")
  mat[b + 1][a + 1] = 1
end
local vec = {}
for i = 1, n do
  vec[i] = 0
end
vec[1] = 1

local tmpmat = {}
for i = 1, n do
  tmpmat[i] = {}
end
local tmpvec = {}

local function matmat()
  for i = 1, n do
    for j = 1, n do
      local v = 0
      for k = 1, n do
        v = bor(v, band(mat[i][k], mat[k][j]))
      end
      tmpmat[i][j] = v
    end
  end
  for i = 1, n do for j = 1, n do
    mat[i][j] = tmpmat[i][j]
  end end
end

local function matvec()
  for i = 1, n do
    local v = 0
    for k = 1, n do
      v = bor(v, band(mat[i][k], vec[k]))
    end
    tmpvec[i] = v
  end
  for i = 1, n do
    vec[i] = tmpvec[i]
  end
end

while 0LL < t do
  if t % 2LL == 1LL then
    matvec()
  end
  matmat()
  t = t / 2LL
end
local z = 0
for i = 1, n do
  z = z + vec[i]
end
print(z)