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Author: prakantsharma

3610-find-x-sum-of-all-k-long-subarrays-i/3610-find-x-sum-of-all-k-long-subarrays-i.cpp

@@ -0,0 +1,43 @@
+class Solution {
+public:
+    using int2=pair<int, int>;
+    static int x_sum( const auto& freq, int k, int x){
+        auto freq2=freq;
+        sort(freq2.begin(), freq2.end(), greater<int2>());
+        int sum=0;
+        for (int i=0; i<x; i++){
+            auto [f, num]=freq2[i];
+            if (f==0) break;
+            sum+=num*f;
+        }
+        return sum;
+    }
+    static vector<int> findXSum(vector<int>& nums, int k, int x) {
+        const int n=nums.size(), sz=n-k+1;
+        vector<int> ans(sz);
+        array<int2, 51> freq;
+        freq.fill({0, 0});
+        for(int r=0; r<k; r++){
+            int z=nums[r];
+            freq[z].second=z;
+            freq[z].first++;
+        }
+        ans[0]=x_sum(freq, k, x);
+        for(int l=1, r=k; l<sz; l++, r++){
+            int L=nums[l-1], R=nums[r];
+            freq[L].first--;
+            freq[R].first++;
+            freq[R].second = R;
+            ans[l]=x_sum(freq, k, x);
+        }
+        return ans;
+    }
+};
+
+
+auto init = []() {
+    ios::sync_with_stdio(0);
+    cin.tie(0);
+    cout.tie(0);
+    return 'c';
+}();