1 files changed, 59 insertions, 0 deletions
diff --git a/codeforces/Odd-EvenIncrements/Odd-EvenIncrements.cpp b/codeforces/Odd-EvenIncrements/Odd-EvenIncrements.cpp
new file mode 100644
index 0000000..dad00f5
--- /dev/null
+++ b/codeforces/Odd-EvenIncrements/Odd-EvenIncrements.cpp
@@ -0,0 +1,59 @@
+#include<bits/stdc++.h>
+using namespace std;
+bool isEvenOrOdd(vector<int> v) {
+  bool even = false;
+  bool odd = false;
+  for(int x : v) {
+    if(x % 2 != 0) {
+      even = false;
+      break;
+    }
+    else{
+      even = true;
+    }
+  }
+  for(int x : v) {
+    if(x % 2 == 0) {
+      odd = false;
+      break;
+    }
+    else{
+      odd = true;
+    }
+  }
+  return odd || even;
+}
+
+int main() {
+  int tt;
+  cin >> tt;
+  while(tt--) {
+    int n;
+    cin >> n;
+    vector<int> v(n);
+    vector<int> vEven;
+    vector<int> vOdd;
+    for(int &x : v) {
+      cin >> x;
+    }
+    bool ok = isEvenOrOdd(v);
+    for(int x : v) {
+      vEven.push_back(x);
+      vOdd.push_back(x);
+    }
+    for(int i = 0; i < v.size(); i++) {
+      if(i % 2 == 0){
+        vEven[i]++;
+      }
+    }
+    bool evenOp = isEvenOrOdd(vEven);
+    for(int i = 0; i < v.size(); i++) {
+      if(i % 2 != 0){
+        vOdd[i]++;
+      }
+    }
+    bool oddOp = isEvenOrOdd(vOdd);
+    cout << (ok ? "YES" : (evenOp || oddOp ? "YES" : "NO")) << endl;
+
+  }
+}