#include <bits/stdc++.h>
#define int long long
#define mod 998244353
using namespace std;
int n, m;
bool e[405][405];
int dp[405][405];
int c[205][205];
signed main()
{
    cin >> n >> m;
    for (int i = 1; i <= m; i++)
    {
        int u, v;
        cin >> u >> v;
        e[u][v] = e[v][u] = true;
    }
    for (int i = 1; i <= 2 * n; i++)
        dp[i][i - 1] = 1;
    c[0][0] = 1;
    for (int i = 1; i <= n; i++)
        for (int j = 0; j <= i; j++)
            if (j == 0 || j == i)
                c[i][j] = 1;
            else
                c[i][j] = c[i - 1][j - 1] + c[i - 1][j], c[i][j] %= mod;
    for (int len = 2; len <= 2 * n; len += 2)
    {
        for (int l = 1, r = l + len - 1; r <= 2 * n; l++, r++)
        {
            if (e[l][r])
                dp[l][r] = dp[l + 1][r - 1];
            for (int k = l + 1; k <= r - 1; k += 2)
                if (e[l][k])
                {
                    dp[l][r] += dp[l + 1][k - 1] *
                                dp[k + 1][r] % mod *
                                c[len / 2][(k - l + 1) / 2] % mod,
                        dp[l][r] %= mod;
                }
        }
    }
    cout << dp[1][2 * n];
    return 0;
}