#include <bits/stdc++.h>
#pragma GCC optimize("unroll-loops")
using namespace std;
using ll=long long;
const int mod=998244353;
#define rep(i,a,b) for (int i=(int)(a);i<(int)(b);i++)

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int N,M;
    cin>>N>>M;
    vector<vector<int>> G(N);
    rep(i,0,M){
        int a,b;
        cin>>a>>b;
        a--,b--;
        G[a].push_back(b);
        G[b].push_back(a);
    }
    vector<ll> dp(N,1);
    ll ans=0;
    vector<int> par(N);
    vector<set<int>> s(N);
    rep(i,0,N) par[i]=i;
    ll val=0;
    auto root=[&](auto self,int var) -> int {
        if(var==par[var]) return var;
        par[var]=self(self,par[var]);
        return par[var];
    };
    auto unite=[&](int a,int b) -> void {
        a=root(root,a);
        b=root(root,b);
        if(s[a].size()<s[b].size()) swap(a,b);
        for(auto x:s[b]){
            if(s[a].count(x)){
                dp[x]=(dp[x]+dp[b]-val)%mod;
            }
            else{
                dp[x]=(dp[x]+dp[b]-dp[a])%mod;
                s[a].insert(x);
            }
        }
        par[b]=a;
    };
    rep(i,0,N){
        set<int> tmp;
        for(auto x:G[i]){
            if(x<i) tmp.insert(root(root,x));
            else s[i].insert(x);
        }
        for(auto x:tmp) dp[i]=(dp[i]+dp[x])%mod;
        for(auto x:tmp) dp[x]=(dp[x]+dp[i])%mod;
        ans=(ans+dp[i])%mod;
        val=dp[i];
        for(auto x:tmp){
            s[x].erase(i);
            unite(i,x);
        }
    }
    cout<<(ans+mod)%mod<<"\n";
}