#include <bits/stdc++.h>
using namespace std;
const long long MOD = 998244353;

int main(void){
    int n, m;
    long long T;
    cin >> n >> m >> T;
    vector<vector<long long>> A(n, vector<long long>(n, 0));
    vector<long long> B(n, 0);
    B[0] = 1;
    int s, t;
    while(m--){
        cin >> s >> t;
        A[s][t] = 1;
        A[t][s] = 1;
    }
    while(T){
        if(T & 1){
            vector<long long> C(n, 0);
            for(int i = 0; i < n; i++) for(int j = 0; j < n; j++){
                C[i] = (C[i] + A[i][j] * B[j]) % MOD;
            }
            B = C;
        }
        T >>= 1;
        vector<vector<long long>> C(n, vector<long long>(n, 0));
        for(int i = 0; i < n; i++) for(int j = 0; j < n; j++){
            for(int k = 0; k < n; k++){
                C[i][j] = (C[i][j] + A[i][k] * A[k][j]) % MOD;
            }
        }
        A = C;
    }
    cout << B[0] << "\n";
}