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_backtracking/permutations_ii.java

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+/**
+ * File: permutations_ii.java
+ * Created Time: 2023-04-24
+ * Author: krahets (krahets@163.com)
+ */
+
+package chapter_backtracking;
+
+import java.util.*;
+
+public class permutations_ii {
+    /* Backtracking algorithm: Permutation II */
+    static void backtrack(List<Integer> state, int[] choices, boolean[] selected, List<List<Integer>> res) {
+        // When the state length equals the number of elements, record the solution
+        if (state.size() == choices.length) {
+            res.add(new ArrayList<Integer>(state));
+            return;
+        }
+        // Traverse all choices
+        Set<Integer> duplicated = new HashSet<Integer>();
+        for (int i = 0; i < choices.length; i++) {
+            int choice = choices[i];
+            // Pruning: do not allow repeated selection of elements and do not allow repeated selection of equal elements
+            if (!selected[i] && !duplicated.contains(choice)) {
+                // Attempt: make a choice, update the state
+                duplicated.add(choice); // Record selected element values
+                selected[i] = true;
+                state.add(choice);
+                // Proceed to the next round of selection
+                backtrack(state, choices, selected, res);
+                // Retract: undo the choice, restore to the previous state
+                selected[i] = false;
+                state.remove(state.size() - 1);
+            }
+        }
+    }
+
+    /* Permutation II */
+    static List<List<Integer>> permutationsII(int[] nums) {
+        List<List<Integer>> res = new ArrayList<List<Integer>>();
+        backtrack(new ArrayList<Integer>(), nums, new boolean[nums.length], res);
+        return res;
+    }
+
+    public static void main(String[] args) {
+        int[] nums = { 1, 2, 2 };
+
+        List<List<Integer>> res = permutationsII(nums);
+
+        System.out.println("Input array nums = " + Arrays.toString(nums));
+        System.out.println("All permutations res = " + res);
+    }
+}