1 files changed, 29 insertions, 0 deletions
diff --git a/contests/Round788/A(2_pointers)/A(2_pointers).cpp b/contests/Round788/A(2_pointers)/A(2_pointers).cpp
new file mode 100755
index 0000000..5d56719
--- /dev/null
+++ b/contests/Round788/A(2_pointers)/A(2_pointers).cpp
@@ -0,0 +1,29 @@
+#include<bits/stdc++.h>
+using namespace std;
+int main () {
+  int tt;
+  cin >> tt;
+  while (tt--) {
+    int n;
+    cin >> n;
+    vector<int> v(n);
+    for(auto &x : v) {
+      cin >> x;
+    }
+    int l = 0, r = v.size() - 1;
+    while(r > l) {
+      while(v[l] < 0) {
+        l++;
+      }
+      while(v[r] > 0) {
+        r--;
+      }
+      if(l > r) break;
+      v[l] = -v[l];
+      v[r] = -v[r];
+    }
+    cout << (is_sorted(v.begin(), v.end()) ? "YES" : "NO");
+  }
+}
+
+