#include <bits/stdc++.h>
#define rep(i,j,k) for(int i=(j);i<=(k);i++)
#define per(i,j,k) for(int i=(j);i>=(k);i--)
#define uint unsigned int
#define ll long long
#define ull unsigned long long
#define db double
#define ldb long double
#define pii pair<int,int>
#define pll pair<ll,ll>
#define mkp make_pair
#define eb emplace_back
#define SZ(S) (int)S.size()
#define mod 998244353
//#define mod 1000000007
#define inf 0x3f3f3f3f
#define linf 0x3f3f3f3f3f3f3f3f
using namespace std;

template <class T>
void chkmax(T &x,T y){
    if(x < y) x = y;
}

template <class T>
void chkmin(T &x,T y){
    if(x > y) x = y;
}

inline int popcnt(int x){
    return __builtin_popcount(x);
}

inline int ctz(int x){
    return __builtin_ctz(x);
}

template <int P>
class mod_int
{
    using Z = mod_int;

private:
    static int mo(int x) { return x < 0 ? x + P : x; }

public:
    int x;
    int val() const { return x; }
    mod_int() : x(0) {}
    template <class T>
    mod_int(const T &x_) : x(x_ >= 0 && x_ < P ? static_cast<int>(x_) : mo(static_cast<int>(x_ % P))) {}
    bool operator==(const Z &rhs) const { return x == rhs.x; }
    bool operator!=(const Z &rhs) const { return x != rhs.x; }
    Z operator-() const { return Z(x ? P - x : 0); }
    Z pow(long long k) const
    {
        Z res = 1, t = *this;
        while (k)
        {
            if (k & 1)
                res *= t;
            if (k >>= 1)
                t *= t;
        }
        return res;
    }
    Z &operator++()
    {
        x < P - 1 ? ++x : x = 0;
        return *this;
    }
    Z &operator--()
    {
        x ? --x : x = P - 1;
        return *this;
    }
    Z operator++(int)
    {
        Z ret = x;
        x < P - 1 ? ++x : x = 0;
        return ret;
    }
    Z operator--(int)
    {
        Z ret = x;
        x ? --x : x = P - 1;
        return ret;
    }
    Z inv() const { return pow(P - 2); }
    Z &operator+=(const Z &rhs)
    {
        (x += rhs.x) >= P && (x -= P);
        return *this;
    }
    Z &operator-=(const Z &rhs)
    {
        (x -= rhs.x) < 0 && (x += P);
        return *this;
    }
    Z operator-()
    {
        return -x;
    }
    Z &operator*=(const Z &rhs)
    {
        x = 1ULL * x * rhs.x % P;
        return *this;
    }
    Z &operator/=(const Z &rhs) { return *this *= rhs.inv(); }
#define setO(T, o)                                  \
    friend T operator o(const Z &lhs, const Z &rhs) \
    {                                               \
        Z res = lhs;                                \
        return res o## = rhs;                       \
    }
    setO(Z, +) setO(Z, -) setO(Z, *) setO(Z, /)
#undef setO
    
    friend istream& operator>>(istream& is, mod_int& x)
    {
        long long tmp;
        is >> tmp;
        x = tmp;
        return is;
    }
    friend ostream& operator<<(ostream& os, const mod_int& x)
    {
        os << x.val();
        return os;
    }
};

using Z = mod_int<mod>;
Z power(Z p,ll k){
    Z ans = 1;
    while(k){
        if(k % 2 == 1) ans *= p;
        p *= p;
        k /= 2;
    }
    return ans;
}
Z fact[1000005],ifac[1000005],inv[1000005];

Z C(int N,int M){
    if(N < M || M < 0) return 0;
    return fact[N] * ifac[M] * ifac[N - M];
}

void init(int L){
    fact[0] = 1;
    rep(i,1,L) fact[i] = fact[i - 1] * i;
    ifac[L] = 1 / fact[L];
    per(i,L - 1,0) ifac[i] = ifac[i + 1] * (i + 1);
    rep(i,1,L) inv[i] = ifac[i] * fact[i - 1];
}
int n,m;

int cnt;
int head[300005];
struct eg{
    int to,nxt;
}edge[600005];

void make(int u,int v){
    edge[++cnt].to = v;
    edge[cnt].nxt = head[u];
    head[u] = cnt;
}

int dfn[300005],low[300005],N;
vector <int> sta,scc[300005];
void tarjan(int u){
    dfn[u] = low[u] = ++cnt;
    sta.eb(u);
    for(int i = head[u];i;i = edge[i].nxt){
        int v = edge[i].to;
        if(!dfn[v]){
//            printf("%d->%d\n",u,v);
            tarjan(v);
            chkmin(low[u],low[v]);
            if(low[v] < dfn[u]) continue;
            ++N;
            while(1){
                int p = sta.back();
                sta.pop_back();
                scc[N].eb(p);
                if(p == v) break;
            }
            scc[N].eb(u);
        }else{
            chkmin(low[u],dfn[v]);
        }
    }
}

vector <int> G[600005];
Z dp[600005],ans;
void dfs(int u,int f){
    dp[u] = 1;
    for(int v:G[u]){
        if(v == f) continue;
        dfs(v,u);
        dp[u] *= dp[v] + 1;
    }
    if(u > n){
        ans += dp[u];
        return;
    }

    dp[u]--;
    ans += dp[u];
    for(int v:G[u]) if(v != f) ans -= dp[v];
}

int main(){
//    freopen("test.in","r",stdin);
    scanf("%d%d",&n,&m);
    rep(i,1,m){
        int u,v;
        scanf("%d%d",&u,&v);
        make(u,v);make(v,u);
    }
    cnt = 0;
    tarjan(1);
//    rep(u,1,n) printf("node %d dfn %d low %d\n",u,dfn[u],low[u]);
    rep(c,1,N){
        for(int u:scc[c]){
//            printf("%d ",u);
            G[u].eb(n + c);
            G[n + c].eb(u);
        }
//        printf("\n");
    }
    dfs(1,0);
    ans += n + 1;
    printf("%d\n",ans.val());
	return 0;
}