#include using namespace std; typedef long long ll; typedef vector VI; typedef vector VVI; typedef vector VL; typedef vector> VVL; typedef pair Pair; typedef tuple tpl; #define ALL(a) (a).begin(),(a).end() #define SORT(c) sort((c).begin(),(c).end()) #define REVERSE(c) reverse((c).begin(),(c).end()) #define EXIST(m,v) (m).find((v)) != (m).end() #define LB(a,x) lower_bound((a).begin(), (a).end(), x) - (a).begin() #define UB(a,x) upper_bound((a).begin(), (a).end(), x) - (a).begin() #define FOR(i,a,b) for(int i=(a);i<(b);++i) #define REP(i,n) FOR(i,0,n) #define RFOR(i,a,b) for(int i=(a)-1;i>=(b);--i) #define RREP(i,n) RFOR(i,n,0) #define en "\n" constexpr double EPS = 1e-9; constexpr double PI = 3.1415926535897932; constexpr int INF = 2147483647; constexpr long long LINF = 1LL<<60; constexpr long long MOD = 998244353; // 1000000007; template inline bool chmax(T& a, T b){if(a inline bool chmin(T& a, T b){if(a>b){a=b;return true;}return false;} #include using mint = atcoder::modint998244353; void Main(){ int N; cin >> N; ll sum = 0; int X = 0; VI A(N); REP(i,N) cin >> A[i], sum += A[i], X ^= A[i]; ll t = 0; if(X == 0) t = sum; else{ t = LINF; REP(i,N) chmin(t, sum + (X^A[i]) - A[i] + 1); } mint ans = mint(2).inv() * (1 - (mint(-1)/3).pow(t)); cout << ans.val() << en; return; } int main(void){ cin.tie(0);cout.tie(0);ios_base::sync_with_stdio(0);cout<>t; while(t--) Main(); return 0; }