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#include <algorithm>
#include <bits/stdc++.h>
#include <tuple>
using namespace std;
using ll = long long;
using pi = pair<int, int>;
using vpi = vector<pi>;
using vi = vector<int>;
using vll = vector<long long>;
using mpii = map<int, int>;
using mpll = map<ll, ll>;
using db = long double;
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define lb lower_bound
#define ub upper_bound
const int MOD = (int)1e9 + 7;
const db PI = acos((db)-1);
const int dx[4]{1, 0, -1, 0};
const int dy[4]{0, 1, 0, -1};
int countVallyes(vi &v) {
int cnt = 0;
for (int i = 1; i < v.size() - 1; i++) {
if (v[i] < v[i - 1] && v[i] < v[i + 1]) {
cnt++;
}
}
return cnt;
}
void solve() {
int n;
cin >> n;
vi v(n + 2);
v[0] = INT_MAX;
v[n + 1] = INT_MAX;
for (int i = 1; i < n + 1; i++) {
cin >> v[i];
}
auto it = unique(all(v));
vi a = vector<int>(v.begin(), it);
cout << (countVallyes(a) == 1 ? "YES" : "NO") << '\n';
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int tt;
cin >> tt;
while (tt--) {
solve();
}
}
/* stuff you should look for:
---------------------------
* special cases (n=1?)
* int overflow, array bounds
* do smth instead of nothing and stay organized
* WRITE STUFF DOWN
* DON'T GET STUCK ON ONE APPROACH
*/
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