def main():
    N,M,T = map(int,input().split())
    e = [[] for _ in range(N)]
    for _ in range(M):
        s,t = map(int,input().split())
        e[s].append(t)
        e[t].append(s)
    mod = 998244353
    def matrix_mul(A,B,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] = sum(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] = sum(A[i][k]*B[k][j]%mod for k in range(mA))%mod
        return tmp
        
    
    def matrix_pow(A,n,mod = None):
        nbit = list(str(bin(n))[2:])
        nbit = [int(i) for i in nbit]
        N = len(A)
        C = [[0]*N for _ in range(N)]
        B = A
        for i in range(N):
            C[i][i] = 1
            
        if mod is None:
            
            for i in range(len(nbit)):
                if nbit[-1-i] == 1:
                    C = matrix_mul(C,B)
                
                B = matrix_mul(B,B)
            return C
            
        for i in range(len(nbit)):
            if nbit[-1-i] == 1:
                C = matrix_mul(C,B,mod)
            
            B = matrix_mul(B,B,mod)
        
        return C
    S = [[0]*N for _ in range(N)]
    for i in range(N):
        for j in e[i]:
            S[i][j] = 1
    tS = matrix_pow(S,T,mod=mod)
    B = [[0] for _ in range(N)]
    B[0] = [1]
    ans = matrix_mul(tS,B,mod=mod)
    print(ans[0][0])
main()