#include using namespace std; using ll = long long; using ld = long double; using V = vector; using VV = vector; using VVV = vector; using VVVV = vector; using VVVVV = vector; using VVVVVV = vector; using VS = vector; using VB = vector; using VVB = vector; using P = pair; using M = map; using Q = queue; using PQ = priority_queue; using PQG = priority_queue>; using S = set; using VP = vector

; const ll MOD = 1000000007; const ll mod = 998244353; const ll INF = 1LL << 60; #define rep(i,n) for(ll i = 0; i < n; i++) #define rep2(i,s,n) for(ll i = s; i < n; i++) #define per(i,n) for(ll i = n-1; i >= 0; i--) #define per2(i,s,n) for(ll i = n-1; i >= s; i--) #define all(x) (x).begin(),(x).end() #define rall(x) (x).rbegin(),(x).rend() #define fi first #define se second #define pb push_back #define pf push_front #define ppb pop_back #define ppf pop_front #define eb emplace_back #define lb lower_bound #define ub upper_bound templatebool chmin(T&a, const T&b){if(a>b){a=b;return 1;}return 0;} templatebool chmax(T&a, const T&b){if(avoid Vin(vector&a){rep(i,(int)a.size())cin>>a[i];} templatevoid VVin(vector>&a){rep(i,(ll)a.size())Vin(a[i]);} templatevoid Vout(const vector&a){rep(i,(int)a.size())cout<0){if(b&1)res=res*a%M;a=a*a%M;b>>=1;}return res;} const ll H[4] = {0,1,0,-1}, W[4] = {1,0,-1,0}; VV f(VV a, VV b) { ll x = a.size(); VV res(x,V(x)); rep(i,x) rep(j,x) rep(k,x) res[i][j] = (res[i][j]+a[i][k]*b[k][j])%mod; return res; } int main() { ll n, m, T; cin >> n >> m >> T; VV G(n,V(n)); rep(i,m) { ll s, t; cin >> s >> t; G[s][t] = G[t][s] = 1; } T--; VV ans = G; while(T > 0) { if(T&1) ans = f(ans,G); G = f(G,G); T >>= 1; } cout << ans[0][0] << endl; }