#include using namespace std; //入力が必ず-mod<=a //mod<2^30. struct modint{ //mod変更が不可能. public: long long v; static void setmod(int m){} //飾り. static constexpr long long getmod(){return mod;} modint():v(0){} template modint(T a):v(a){if(v < 0) v += mod;} long long val()const{return v;} modint &operator=(const modint &b) = default; modint &operator+()const{return (*this);} modint operator-()const{return modint(0)-(*this);} modint operator+(const modint b)const{return modint(v)+=b;} modint operator-(const modint b)const{return modint(v)-=b;} modint operator*(const modint b)const{return modint(v)*=b;} modint operator/(const modint b)const{return modint(v)/=b;} modint &operator+=(const modint b){ v += b.v; if(v >= mod) v -= mod; return *this; } modint &operator-=(const modint b){ v -= b.v; if(v < 0) v += mod; return *this; } modint &operator*=(const modint b){v = v*b.v%mod; return *this;} modint &operator/=(modint b){ //b!=0 mod素数が必須. assert(b.v != 0); (*this) *= b.pow(mod-2); return *this; } modint pow(long long n)const{ modint ret = 1,p = v; if(n < 0) p = p.inv(),n = -n; while(n){ if(n&1) ret *= p; p *= p; n >>= 1; } return ret; } modint inv()const{return pow(mod-2);} //素数mod必須. modint &operator++(){*this += 1; return *this;} modint &operator--(){*this -= 1; return *this;} modint operator++(int){modint ret = *this; *this += 1; return ret;} modint operator--(int){modint ret = *this; *this -= 1; return ret;} friend bool operator==(const modint a,const modint b){return a.v==b.v;} friend bool operator!=(const modint a,const modint b){return a.v!=b.v;} friend bool operator<(const modint a,const modint b){return a.v=(const modint a,const modint b){return a.v>=b.v;} friend bool operator>(const modint a,const modint b){return a.v>b.v;} friend ostream &operator<<(ostream &os,const modint a){return os<>(istream &is,modint &a){ //入力はmodをとってくれる. long long x; is >> x; x %= mod; a = modint(x); return is; } }; using mint = modint<998244353>; const long long mod = 998244353; int main(){ ios_base::sync_with_stdio(false); cin.tie(nullptr); int T; cin >> T; while(T--){ int N; cin >> N; vector> Graph(N); for(int i=0; i> u >> v; u--; v--; Graph.at(u).push_back(v); Graph.at(v).push_back(u); } mint answer = 0; auto dfs = [&](auto dfs,int pos,int back) -> pair { vector Two; int two = 0,three = 0; vector dp(4); dp.at(0) = 1; for(auto to : Graph.at(pos)){ if(to == back) continue; auto [k2,k3] = dfs(dfs,to,pos); three += k2,two++; answer += k3; vector next = dp; for(int i=0; i<4; i++){ if(i == 0 || i == 2) next.at(i+1) += dp.at(i); if(i == 0 || i == 1) next.at(i+2) += dp.at(i)*k2; } swap(dp,next); } answer += dp.at(3); return {two,three}; }; dfs(dfs,0,-1); cout << answer << "\n"; } }