Update remove min :: min heap sort

priority queues/remove min :: min heap sort

@@ -48,7 +48,7 @@ class PriorityQueue {
 
     }
 
-
+   /* 
     int removeMin() {
         // Complete this function
         if(pq.size()==0)
@@ -110,6 +110,41 @@ class PriorityQueue {
       }
         return m;
     }
+    */
+    //I feel this code is much more easy to understand and also organised
 
-
+    int removeMin() {
+        int ans = pq[0];//placing root node which is min in the ans, which we will return in last
+
+        pq[0]=pq[pq.size()-1];//coping last element in place of root node
+
+        pq.pop_back();//removing the last element space
+
+        int pi = 0,LCI = 2*pi+1,RCI = 2*pi+2;//parent index, left child index, right child index
+
+        // now we need to perform down hepify
+       //we need to get minimum of parent and children
+
+        while(LCI<pq.size())//we check if lci is within limit or not
+        {
+            int minIndex = pi;//minIndex will be the index carrying the min value...out of 3
+            if(pq[minIndex]>pq[LCI])
+                minIndex = LCI;
+            //check if rci is also with in limit or not
+            if(RCI<pq.size() && pq[minIndex]>pq[RCI])
+                minIndex = RCI;
+            //if both of the above if do not run then it means we dont need to swap anymore
+            if(pi == minIndex)
+                break;
+            //now we got the index with which we need to swapp so do it
+            int temp = pq[pi];
+            pq[pi] = pq[minIndex];
+            pq[minIndex] = temp;
+            //now update pi,lci,rci
+            pi=minIndex;//because after swapping the number is at minIndex...so it will be our new pi
+            LCI=2*pi+1;
+            RCI=2*pi+2;
+        }
+        return ans;
+    }
 };