B - Rising Sand

https://codeforces.com/contest/1698/submission/162069282

Codeforces/1698/B/B.cpp

@@ -0,0 +1,38 @@
+#include <iostream>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 2e5 + 5;
+
+int t, n, k, a[N];
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> t;
+
+    while (t--) {
+        int cnt = 0;
+
+        cin >> n >> k;
+
+        for (int i = 1; i <= n; i++) {
+            cin >> a[i];
+        }
+
+        for (int i = 2; i < n; i++) {
+            if (a[i - 1] + a[i + 1] < a[i]) cnt++;
+        }
+
+        if (k == 1) {
+            cout << (n - 1) / 2 << endl;
+        } else {
+            cout << cnt << endl;
+        }
+    }
+
+    return 0;
+}