Knapsack problem

Greedy Algorithms/fractionalKnapsack.java

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+import java.lang.*;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.Scanner;
+// Greedy approach
+public class fractionalKnapsack {
+
+    // Function to get maximum value
+    private static double getMaxValue(ItemValue[] arr,int capacity)
+    {
+        // 1. Sorting items by profit/weight ratio;
+        Arrays.sort(arr, new Comparator<ItemValue>() {
+            public int compare(ItemValue item1,ItemValue item2)
+            {
+                double cpr1 = Double.valueOf(item1.profit/item1.weight);
+                double cpr2 = Double.valueOf(item2.profit/item2.weight);
+
+                if (cpr1 < cpr2)
+                    return 1;
+                else
+                    return -1;
+            }
+        });
+
+        double totalValue = 0;
+
+        for (ItemValue i : arr) {
+
+            int curWt = (int)i.weight;
+            int curProfit = (int)i.profit;
+
+            if (capacity - curWt >= 0) {
+
+                // This weight can be picked whole
+                capacity = capacity - curWt;
+                totalValue += curProfit;
+            }
+            else {
+
+                // Item cant be picked whole
+                double fraction = ((double)capacity / (double)curWt);
+                totalValue += (curProfit * fraction);
+                capacity= (int)(capacity - (curWt * fraction));
+                break;
+            }
+        }
+
+        return totalValue;
+    }
+
+    // Item value class
+    static class ItemValue {
+
+        int profit, weight;
+        // Item value function
+        // public ItemValue(int profit, int wt)
+        // {
+        //     this.weight = wt;
+        //     this.profit = profit;
+        // }
+    }
+
+    // Driver code
+    public static void main(String[] args)
+    {
+        Scanner sc=new Scanner(System.in);
+        System.out.println("Enter the no. of objects");
+        int n=sc.nextInt();
+        ItemValue[] arr=new ItemValue[n];
+
+        for(int i=0;i<n;i++){
+            System.out.println("Enter the profit ans corresponding weight");
+            arr[i]=new ItemValue();
+            arr[i].profit=sc.nextInt();
+            arr[i].weight=sc.nextInt();
+        }
+
+        System.out.println("Enter the max capacity");
+        int capacity =sc.nextInt();
+
+        //function calling
+        double maxValue = getMaxValue(arr, capacity);
+
+        // Function call
+        System.out.println("Maximum Profit is: "+maxValue);
+    }
+}