Merge pull request #341 from gulshanyadav01/gulshan

k closest has been done

Author: gulshanyadav01

Heap/a.out

@@ -0,0 +1,76 @@
+/*
+author:gulshan yadav
+email: gulshany01@gmail.com
+date: 21-July-2021
+*/
+#include<iostream>
+#include<bits/stdc++.h>
+using namespace std;
+
+
+// this is the naive approach 
+// Time : O(NK)
+// Aux : O(N)
+void kClosest(int arr[], int num, int k,int x ){
+
+    // iter to the kth time
+    bool visited[num] = {false};
+    for(int i = 0; i< k; i++){
+
+        
+        int minDiff = INT_MAX; 
+        int minInd; 
+        for(int j = 0; j< num; j++){
+            if((visited[j] == false) && (abs(arr[j]-x) <= minDiff)){
+                minDiff = abs(arr[j]-x);
+                minInd = j;
+
+            }
+        }
+        // print the value 
+        cout << arr[minInd]<<" ";
+        visited[minInd] = true; 
+    }
+}
+
+
+// efficieint solution 
+void kClosest2(int arr[], int num, int k, int x){
+    // create a max heap;
+    priority_queue<pair<int, int>> pq; 
+
+    for(int i = 0; i< k; i++){
+        pq.push({abs(arr[i]-x), i});
+
+    }
+
+    for(int i = k; i< num; i++){
+        int minDiff = abs(arr[i]-x); 
+        if(pq.top().first > minDiff){
+            pq.pop(); 
+            pq.push({minDiff, i}); 
+        }
+    }
+    // print the value 
+
+    while(pq.empty() == false){
+        cout << arr[pq.top().second]<< " ";
+        pq.pop(); 
+    }
+
+}
+
+int main(){
+    int num; 
+    cin >> num; 
+    int arr[num];
+    for(int i =0; i<  num; i++){
+        cin >> arr[i]; 
+    }
+    int k, x; 
+    cin >> k>> x; 
+    kClosest(arr, num, k, x);
+    cout << endl;
+    kClosest2(arr, num, k, x); 
+    return 0; 
+}