translation: Add Python and Java code for EN version (#1345)

* Add the intial translation of code of all the languages

* test

* revert

* Remove

* Add Python and Java code for EN version

en/codes/java/chapter_greedy/fractional_knapsack.java

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+/**
+ * File: fractional_knapsack.java
+ * Created Time: 2023-07-20
+ * Author: krahets (krahets@163.com)
+ */
+
+package chapter_greedy;
+
+import java.util.Arrays;
+import java.util.Comparator;
+
+/* Item */
+class Item {
+    int w; // Item weight
+    int v; // Item value
+
+    public Item(int w, int v) {
+        this.w = w;
+        this.v = v;
+    }
+}
+
+public class fractional_knapsack {
+    /* Fractional knapsack: Greedy */
+    static double fractionalKnapsack(int[] wgt, int[] val, int cap) {
+        // Create an item list, containing two properties: weight, value
+        Item[] items = new Item[wgt.length];
+        for (int i = 0; i < wgt.length; i++) {
+            items[i] = new Item(wgt[i], val[i]);
+        }
+        // Sort by unit value item.v / item.w from high to low
+        Arrays.sort(items, Comparator.comparingDouble(item -> -((double) item.v / item.w)));
+        // Loop for greedy selection
+        double res = 0;
+        for (Item item : items) {
+            if (item.w <= cap) {
+                // If the remaining capacity is sufficient, put the entire item into the knapsack
+                res += item.v;
+                cap -= item.w;
+            } else {
+                // If the remaining capacity is insufficient, put part of the item into the knapsack
+                res += (double) item.v / item.w * cap;
+                // No remaining capacity left, thus break the loop
+                break;
+            }
+        }
+        return res;
+    }
+
+    public static void main(String[] args) {
+        int[] wgt = { 10, 20, 30, 40, 50 };
+        int[] val = { 50, 120, 150, 210, 240 };
+        int cap = 50;
+
+        // Greedy algorithm
+        double res = fractionalKnapsack(wgt, val, cap);
+        System.out.println("The maximum value within the bag capacity is " + res);
+    }
+}