func_code_string: #include <algorithm>   #include <iostream>   #include <cstdlib>   #include <cassert>   #include <cstring>   #include <iomanip>   #include <cstdio>   #include <limits>   #include <string>   #include <vector>   #include <cmath>   #include <deque>   #include <queue>   #include <stack>   #include <map>   #include <set>   using namespace std;      typedef long long LL;   typedef long long ll;   typedef long double LD;   typedef vector<int> vi;   typedef pair<LL,LL> PLL;   typedef pair<LL,int> PLI;   typedef pair<int,int> PII;   typedef pair<int,int> pii;   typedef vector<vector<LL>> VVL;      #define rep(i, a, b) for(int i = a; i < (b); ++i)   #define trav(a, x) for(auto& a : x)   #define all(x) begin(x), end(x)   #define sz(x) (int)(x).size()   #define popf pop_front   #define pf push_front   #define popb pop_back   #define mp make_pair   #define pb push_back   #define remove erase   #define fi first   #define se second      #define endl   n       const int INF = 1061109567;   const LL LINF = 4557430888798830399LL;   const LL MOD = 1000000007;   const int dx[8] = {0,0,1,-1,1,-1,1,-1};   const int dy[8] = {1,-1,0,0,1,-1,-1,1};   const char dch[4] = { R , L , D , U };   // const string ds[8] = { E , W , S , N , SE , NW , SW , NE };   inline void fasterios(){       ios_base::sync_with_stdio(0);       cin.tie(0); cout.tie(0);   }         // Don t forget to read all the inputs before returning!!!   int solve(){     int n; cin >> n;     vector <PII> arr(n);     rep(i,0,n){       cin >> arr[i].fi;       arr[i].se = i;     }     sort(all(arr));     vector <int> tmp[2];     rep(i,0,n) if(abs(arr[i].se - i) % 2 == 1) tmp[i%2].pb(arr[i].fi);     sort(all(tmp[0]));     sort(all(tmp[1]));     if(sz(tmp[0]) != sz(tmp[1])){       cout <<  NO  << endl;       return 0;     }     for(int i = 0;i < sz(tmp[0]);i++){       if(tmp[0][i] != tmp[1][i]){         cout <<  NO  << endl;         return 0;       }     }     cout <<  YES  << endl;     return 0;   }      int main(){     fasterios();     int testCases; cin >> testCases; int tc = 0;     while(++tc <= testCases){       // cout <<  Case #  << tc <<  :  ;       solve();     }   }