import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		long t = sc.nextLong();
		long[][] a = new long[n][n];
		for (int i = 0; i < m; i++) {
			int u = sc.nextInt();
			int v = sc.nextInt();
			a[u][v] = 1;
			a[v][u] = 1;
		}
		sc.close();

		int mod = 998244353;
		long[][] b = matrixPow(a, t, mod);
		long[] c = new long[n];
		c[0] = 1;
		long[] d = matrixMul1(c, b, mod);
		System.out.println(d[0]);
	}

	static long[][] matrixPow(long[][] a, long k, int m) {
		if (k == 1) {
			return a;
		}
		long[][] ret = matrixPow(a, k / 2, m);
		ret = matrixMul(ret, ret, m);
		if (k % 2 == 1) {
			ret = matrixMul(ret, a, m);
		}
		return ret;
	}

	static long[][] matrixMul(long[][] a, long[][] b, int m) {
		int h = a.length;
		int w = b[0].length;
		int n = a[0].length;
		long[][] c = new long[h][w];
		for (int i = 0; i < h; i++) {
			for (int j = 0; j < w; j++) {
				for (int x = 0; x < n; x++) {
					c[i][j] += a[i][x] * b[x][j];
					c[i][j] %= m;
				}
			}
		}
		return c;
	}

	static long[] matrixMul1(long[] a, long[][] b, int m) {
		int w = b[0].length;
		int n = a.length;
		long[] c = new long[w];
		for (int j = 0; j < w; j++) {
			for (int x = 0; x < n; x++) {
				c[j] += a[x] * b[x][j];
				c[j] %= m;
			}
		}
		return c;
	}
}