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_divide_and_conquer/binary_search_recur.java

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+/**
+ * File: binary_search_recur.java
+ * Created Time: 2023-07-17
+ * Author: krahets (krahets@163.com)
+ */
+
+package chapter_divide_and_conquer;
+
+public class binary_search_recur {
+    /* Binary search: problem f(i, j) */
+    static int dfs(int[] nums, int target, int i, int j) {
+        // If the interval is empty, indicating no target element, return -1
+        if (i > j) {
+            return -1;
+        }
+        // Calculate midpoint index m
+        int m = (i + j) / 2;
+        if (nums[m] < target) {
+            // Recursive subproblem f(m+1, j)
+            return dfs(nums, target, m + 1, j);
+        } else if (nums[m] > target) {
+            // Recursive subproblem f(i, m-1)
+            return dfs(nums, target, i, m - 1);
+        } else {
+            // Found the target element, thus return its index
+            return m;
+        }
+    }
+
+    /* Binary search */
+    static int binarySearch(int[] nums, int target) {
+        int n = nums.length;
+        // Solve problem f(0, n-1)
+        return dfs(nums, target, 0, n - 1);
+    }
+
+    public static void main(String[] args) {
+        int target = 6;
+        int[] nums = { 1, 3, 6, 8, 12, 15, 23, 26, 31, 35 };
+
+        // Binary search (double closed interval)
+        int index = binarySearch(nums, target);
+        System.out.println("Index of target element 6 =" + index);
+    }
+}

en/codes/java/chapter_divide_and_conquer/build_tree.java

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+/**
+ * File: build_tree.java
+ * Created Time: 2023-07-17
+ * Author: krahets (krahets@163.com)
+ */
+
+package chapter_divide_and_conquer;
+
+import utils.*;
+import java.util.*;
+
+public class build_tree {
+    /* Build binary tree: Divide and conquer */
+    static TreeNode dfs(int[] preorder, Map<Integer, Integer> inorderMap, int i, int l, int r) {
+        // Terminate when subtree interval is empty
+        if (r - l < 0)
+            return null;
+        // Initialize root node
+        TreeNode root = new TreeNode(preorder[i]);
+        // Query m to divide left and right subtrees
+        int m = inorderMap.get(preorder[i]);
+        // Subproblem: build left subtree
+        root.left = dfs(preorder, inorderMap, i + 1, l, m - 1);
+        // Subproblem: build right subtree
+        root.right = dfs(preorder, inorderMap, i + 1 + m - l, m + 1, r);
+        // Return root node
+        return root;
+    }
+
+    /* Build binary tree */
+    static TreeNode buildTree(int[] preorder, int[] inorder) {
+        // Initialize hash table, storing in-order elements to indices mapping
+        Map<Integer, Integer> inorderMap = new HashMap<>();
+        for (int i = 0; i < inorder.length; i++) {
+            inorderMap.put(inorder[i], i);
+        }
+        TreeNode root = dfs(preorder, inorderMap, 0, 0, inorder.length - 1);
+        return root;
+    }
+
+    public static void main(String[] args) {
+        int[] preorder = { 3, 9, 2, 1, 7 };
+        int[] inorder = { 9, 3, 1, 2, 7 };
+        System.out.println("Pre-order traversal = " + Arrays.toString(preorder));
+        System.out.println("In-order traversal = " + Arrays.toString(inorder));
+
+        TreeNode root = buildTree(preorder, inorder);
+        System.out.println("The built binary tree is:");
+        PrintUtil.printTree(root);
+    }
+}

en/codes/java/chapter_divide_and_conquer/hanota.java

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+/**
+ * File: hanota.java
+ * Created Time: 2023-07-17
+ * Author: krahets (krahets@163.com)
+ */
+
+package chapter_divide_and_conquer;
+
+import java.util.*;
+
+public class hanota {
+    /* Move a disc */
+    static void move(List<Integer> src, List<Integer> tar) {
+        // Take out a disc from the top of src
+        Integer pan = src.remove(src.size() - 1);
+        // Place the disc on top of tar
+        tar.add(pan);
+    }
+
+    /* Solve the Tower of Hanoi problem f(i) */
+    static void dfs(int i, List<Integer> src, List<Integer> buf, List<Integer> tar) {
+        // If only one disc remains on src, move it to tar
+        if (i == 1) {
+            move(src, tar);
+            return;
+        }
+        // Subproblem f(i-1): move the top i-1 discs from src with the help of tar to buf
+        dfs(i - 1, src, tar, buf);
+        // Subproblem f(1): move the remaining one disc from src to tar
+        move(src, tar);
+        // Subproblem f(i-1): move the top i-1 discs from buf with the help of src to tar
+        dfs(i - 1, buf, src, tar);
+    }
+
+    /* Solve the Tower of Hanoi problem */
+    static void solveHanota(List<Integer> A, List<Integer> B, List<Integer> C) {
+        int n = A.size();
+        // Move the top n discs from A with the help of B to C
+        dfs(n, A, B, C);
+    }
+
+    public static void main(String[] args) {
+        // The tail of the list is the top of the pillar
+        List<Integer> A = new ArrayList<>(Arrays.asList(5, 4, 3, 2, 1));
+        List<Integer> B = new ArrayList<>();
+        List<Integer> C = new ArrayList<>();
+        System.out.println("Initial state:");
+        System.out.println("A = " + A);
+        System.out.println("B = " + B);
+        System.out.println("C = " + C);
+
+        solveHanota(A, B, C);
+
+        System.out.println("After the discs are moved:");
+        System.out.println("A = " + A);
+        System.out.println("B = " + B);
+        System.out.println("C = " + C);
+    }
+}