Create main.cpp

Author: JawadSher

19 - Heap Data Structure Problems/14 - Smallest Range in K Lists/main.cpp

@@ -0,0 +1,62 @@
+class Node{
+    public:
+        int data;
+        int row;
+        int col;
+        
+        Node(int data, int row, int col){
+            this -> data = data;
+            this -> row = row;
+            this -> col = col;
+        }
+};
+
+class compare{
+    public:
+        bool operator()(Node* a, Node* b){
+            return a -> data > b -> data;
+        }
+};
+class Solution{
+    public:
+    pair<int,int> findSmallestRange(int arr[][N], int n, int k)
+    {
+        int mini = INT_MAX;
+        int maxi = INT_MIN;
+        
+        priority_queue<Node*, vector<Node*>, compare> minHeap;
+        
+        for(int i = 0; i < k; i++){
+            int element = arr[i][0];  
+            
+            mini = min(mini, element);
+            maxi = max(maxi, element);
+            
+            minHeap.push(new Node(element, i, 0));
+        }
+        
+        
+        int start = mini, end = maxi;
+        
+        while(!minHeap.empty()){
+            Node* temp = minHeap.top();
+            minHeap.pop();
+            
+            mini = temp -> data;
+            
+            if(maxi - mini < end - start){
+                start = mini;
+                end = maxi;
+            }
+            
+            if(temp -> col + 1 < n){
+                maxi = max(maxi, arr[temp->row][temp->col + 1]);
+                minHeap.push(new Node(arr[temp->row][temp->col + 1], temp -> row, temp -> col + 1));
+            }else break;
+            
+        }
+        
+        return {start, end};
+        
+    }
+};