From a1c1695ab55f52deb9c46751111aea58b525ec96 Mon Sep 17 00:00:00 2001
From: Nitin Rajpoot <nitinrajpoot.dev@gmail.com>
Date: Tue, 28 Oct 2025 16:19:45 +0530
Subject: [PATCH] Add solution for distinct values subarrays II

---
 .../distinct_values_subarrays_II.cpp          | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)
 create mode 100644 2_sorting_searching/distinct_values_subarrays_II.cpp

diff --git a/2_sorting_searching/distinct_values_subarrays_II.cpp b/2_sorting_searching/distinct_values_subarrays_II.cpp
new file mode 100644
index 0000000..6892ac3
--- /dev/null
+++ b/2_sorting_searching/distinct_values_subarrays_II.cpp
@@ -0,0 +1,45 @@
+// Problem: Distinct Values Subarrays II
+// Category: Sorting and Searching
+// Difficulty: Medium
+// Time Complexity: O(n)
+// Space Complexity: O(n)
+
+// Approach:
+// Use a sliding window [l, r] to maintain at most k distinct elements.
+// Track frequencies using a hash map.
+// Expand r, and when distinct elements exceed k, move l forward.
+// For each r, add (r - l + 1) to the answer (all valid subarrays ending at r).
+
+#include <bits/stdc++.h>
+using namespace std;
+
+int main() {
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    int n, k;
+    cin >> n >> k;
+    vector<int> a(n);
+    for (int i = 0; i < n; i++) cin >> a[i];
+
+    long long ans = 0;
+    unordered_map<int, int> freq;
+    int left = 0;
+    int distinct = 0;
+
+    for (int right = 0; right < n; right++) {
+        if (freq[a[right]] == 0) distinct++;
+        freq[a[right]]++;
+
+        while (distinct > k) {
+            freq[a[left]]--;
+            if (freq[a[left]] == 0) distinct--;
+            left++;
+        }
+
+        ans += (right - left + 1);
+    }
+
+    cout << ans << "\n";
+    return 0;
+}