import sys
input = lambda : sys.stdin.readline().rstrip()

sys.setrecursionlimit(2*10**5+10)
write = lambda x: sys.stdout.write(x+"\n")
_print = lambda *x: print(*x, file=sys.stderr)

### 行列積 matrix multiplication
### 繰り返し2乗法 kurikae

M = 10**9+7
def mul(a,b):
    """行列a,bの積
    aかbがNone のとき、単位行列として扱う
    """
    if a is None:
        return b
    elif b is None:
        return a
    n,m = len(a), len(a[0])
    k,l = len(b), len(b[0])
    # k==m
    out = [[0]*l for _ in range(n)]
    for i in range(n):
        for j in range(l):
            for p in range(m):
                out[i][j] |= (a[i][p]&b[p][j])
    return out
def mulk(m, k):
    """a^kを求める
    """
    ans = None
    tmp = m
    while k>0:
        if k&1:
            ans = mul(ans, tmp)
        tmp = mul(tmp, tmp)
        k = k>>1
    return ans
def mul2(m,a):
    """行列と配列の積
    """
    k,l = len(m), len(m[0])
#     ll = len(a)
    ans = [0]*k
    for i in range(k):
        for j in range(l):
            ans[i] |= (m[i][j] & a[j])
    return ans

n,m,t = list(map(int, input().split()))
val = [[0]*n for _ in range(n)]
for i in range(m):
    a,b = map(int, input().split())
    val[a][b] = 1
if t==0:
    print(1)
else:
    valt = mulk(val,t)
    b = [0]*n
    b[0] = 1
    valtt = [[0]*n for _ in range(n)]
    for i in range(n):
        for j in range(n):
            valtt[i][j] = valt[j][i]
    ans = mul2(valtt,b)
    print(sum(ans))