import sys
input=sys.stdin.readline

N,M,T=map(int,input().split())
Mod=998244353

E=[]
for _ in range(M):
    s,t=map(int,input().split())
    E.append((s,t))

DP=[0]*N; DP[0]=1
D=[0]*N

for _ in range(T):
    for k in range(N):
        D[k]=DP[k]%Mod
        DP[k]=0

    for s,t in E:
        DP[s]+=D[t]
        DP[t]+=D[s]

print(DP[0]%Mod)