n,m,t = map(int,input().split())
mod = 998244353

path = [[0]*n for i in range(n)]
edge = [[int(x) for x in input().split()] for i in range(m)]
for u,v in edge:
    path[u][v] = path[v][u] = 1



def calc(a,b):
    ans = [[0]*n for i in range(n)]
    for i in range(n):
        for j in range(n):
            for k in range(n):
                ans[i][j] += a[i][k]*b[k][j]
                ans[i][j] %= mod
    return ans


base = [[0]*n for i in range(n)]
for i in range(n):
    base[i][i] = 1


while t:
    if t%2:
        base = calc(base,path)
    path = calc(path,path)
    t //= 2

print(base[0][0])