efficient approch to find minimum alloction of page to the student

Raushan-Kumar007 · Jun 22, 2022 · eed13fd · eed13fd
1 parent a419362
commit eed13fd
Showing 1 changed file with 38 additions and 1 deletion.
diff --git a/Searching/AllocatedMinimumPage.java b/Searching/AllocatedMinimumPage.java
@@ -4,7 +4,7 @@ public class AllocatedMinimumPage {
 
     // Naive APPROCH--------->>>>> THIS APPROCH IS VERY SLOW TIME COMPLEXITY IS EXPONENTIAL
 
-     static int minPage(int arr[],int n, int k){  
+    /*  static int minPage(int arr[],int n, int k){  
         if(k==1)
         return sum(arr,0,n-1);
         if(n==1)
@@ -21,6 +21,43 @@ static int sum(int arr[], int b, int e){
           s += arr[i];
         }
         return s;
+    }*/
+
+// Efficient approch to find aloction of minimum page using binaray search with time complexity is BigO(n*log(sum-max))
+
+    static int minPage(int arr[], int n,int k){
+        int sum = 0;
+        int max = 0;
+        for(int i=0;i<n;i++){
+            sum += arr[i];
+            max = Math.max(max,arr[i]);
+        }
+        int low = max;
+        int high = sum;
+        int res = 0;
+        while(low<=high){
+            int mid = (low+high)/2;
+            if(isfavrable(arr,n,k,mid)){
+                res=mid;
+                high=mid-1;
+            }else{
+                low = mid+1;
+            }
+        }
+        return res;
+    }
+    static boolean isfavrable(int arr[],int n,int k, int ans){
+        int req = 1;
+        int sum = 0;
+        for(int i=0;i<n;i++){
+            if(sum+arr[i]>ans){
+                req++;
+                sum = arr[i];
+            }else{
+                sum += arr[i];
+            }
+        }
+        return (req<=k);
     }
    public static void main(String[] args) {
     int arr[]={10,20,10,30};