from functools import reduce


##fの単位元を要考慮、matrix_powのCの初期化

def f(x,y):
    return x|y
def g(x,y):
    return x&y
def matrix_mul(A,B,f,g,mod = None):
    nA = len(A)
    mA = len(A[0])
    mB = len(B[0])
    
    tmp = [[0]*mB for _ in range(nA)]
    
    if mod is None:
        for i in range(nA):
            for j in range(mB):
                tmp[i][j] = reduce(f,(g(A[i][k],B[k][j]) for k in range(mA)))
                
        return tmp
    
    for i in range(nA):
        for j in range(mB):
            tmp[i][j] = reduce(f,(g(A[i][k],B[k][j])%mod for k in range(mA)))%mod
    return tmp
    

def matrix_pow(A,n,f,g,mod = None):
    nbit = list(str(bin(n))[2:])
    nbit = [int(i) for i in nbit]
    N = len(A)
    C = [[False]*N for _ in range(N)]
    B = A
    for i in range(N):
        C[i][i] = True
        
    if mod is None:
        if f is None:
            for i in range(len(nbit)):
                if nbit[-1-i] == 1:
                    C = matrix_mul(C,B,f,g)
                
                B = matrix_mul(B,B,f,g)
            return C
        
    for i in range(len(nbit)):
        if nbit[-1-i] == 1:
            C = matrix_mul(C,B,f,g,mod=mod)
        
        B = matrix_mul(B,B,f,g,mod=mod)
    
    return C
    
N,M,T = map(int,input().split())
A = [[False]*N for _ in range(N)]

for _ in range(M):
    a,b = map(int,input().split())
    A[b][a] = True

INIT = [[False] for _ in range(N)]
INIT[0] = [True]

X = matrix_pow(A,T,f,g)
Y = matrix_mul(X,INIT,f,g)
ans = sum(int(*Y[i]) for i in range(N))
#print(*Y[0])
print(ans)