import sys
input = sys.stdin.readline

def Matprod(A, B, mod, N):
    temp = [0] * N*N
    for i in range(N):
        for j in range(N):
            ij = i * N + j
            for k in range(N):
                temp[ij] += A[i*N+k] * B[k*N+j]
                temp[ij] %= mod
    return temp

def Matpow_Linear(A, M, mod, N):
    Mat = [0] * N*N
    for i in range(N):
        Mat[i*N+i] = 1
         
    while M:
        if M & 1:
            Mat = Matprod(Mat, A, mod, N)
        A = Matprod(A, A, mod, N)
        M >>= 1
    return Mat  

N, M, T = map(int, input().split())
N2 = N * N
dp = [0] * N2
for i in range(M):
    a, b = map(int, input().split())
    dp[a*N+b] += 1
    
mod = 999999937
dp = Matpow_Linear(dp, T, mod, N)
ans = 0
for i in range(N):
    if dp[i]:
        ans += 1
        
print(ans)