Fractional Knapsack

/*
class Item {
    int value, weight;
    Item(int x, int y){
        this.value = x;
        this.weight = y;
    }
}
*/


class itemComparator implements Comparator<Item>
{

    public int compare(Item a, Item b)
    {
        double r1 = (double)a.value / a.weight;
        double r2 = (double)b.value / b.weight;
        
        if(r1 > r2)
        {
            
            
            return -1;
        } 
        else if(r1 < r2) 
        {
            
            return 1;
            
        }
        
        
        return 0;
    }
}

class Solution
{
    //Function to get the maximum total value in the knapsack.
    double fractionalKnapsack(int W, Item arr[], int n) 
    {
        // Your code here
        
        Arrays.sort(arr, new itemComparator());
        
        int curWeight = 0;
        double finalvalue = 0.0;
        
        for (int i = 0; i < n; i++) 
        {
            
            
            if (curWeight + arr[i].weight <= W) 
            {
                curWeight += arr[i].weight;
                finalvalue += arr[i].value;
                
                
            } 
            else 
            {
                int remain = W - curWeight;
                finalvalue += arr[i].value * ((double) remain / arr[i].weight);
                break;
                
            }
            
            
        }
        return finalvalue;

        
        
        
        
        
        
        
        
        
        
    }
}