func_code_string: #include<bits/stdc++.h>   #define ll long long   #define L(i, j, k) for(int i = (j); i <= (k); ++i)   #define R(i, j, k) for(int i = (j); i >= (k); --i)   #define vi vector < int >    #define sz(a) ((int) a.size())    using namespace std;   const int N = 1e6 + 7;   int T;      int n, m, c[N], a[N], b[N];    void Main () {    n = m = 0;    int x;    cin >> x;    L(i, 1, x) {     int w;     cin >> w;     c[i] = w;     if(i & 1) a[++n] = w;     else b[++m] = w;    }    sort(a + 1, a + n + 1);    sort(b + 1, b + m + 1);    sort(c + 1, c + x + 1);    n = 0, m = 0;    L(i, 1, x) {     if(i & 1) {      if(a[++n] != c[i]) return cout <<  NO n , void();     }     else {      if(b[++m] != c[i]) return cout <<  NO n , void();     }     }    cout <<  YES n ;   }   int main() {     ios::sync_with_stdio(false);    cin.tie(0); cout.tie(0);    cin >> T;    while (T--) Main();    return 0;   }