[N-0] refactor 77

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_77.java

@@ -4,7 +4,10 @@
 import java.util.ArrayList;
 import java.util.List;
 
-/**Given two integers n and k, return all possible combinations of k numbers out of 1 ... n.
+/**
+ * 77. Combinations
+ *
+ * Given two integers n and k, return all possible combinations of k numbers out of 1 ... n.
 
  For example,
  If n = 4 and k = 2, a solution is:
@@ -16,8 +19,11 @@
  [1,2],
  [1,3],
  [1,4],
- ]*/
+ ]
+ */
+
 public class _77 {
+
     public List<List<Integer>> combine(int n, int k) {
         List<List<Integer>> result = new ArrayList();
         int[] nums = new int[n];
@@ -28,15 +34,14 @@ public List<List<Integer>> combine(int n, int k) {
         return result;
     }
 
-    void backtracking(int k, int start, int[] nums, List<Integer> temp, List<List<Integer>> result) {
-        if (temp.size() == k) {
-            List<Integer> newTemp = new ArrayList(temp);
-            result.add(newTemp);
-        } else if (temp.size() < k) {
+    void backtracking(int k, int start, int[] nums, List<Integer> curr, List<List<Integer>> result) {
+        if (curr.size() == k) {
+            result.add(new ArrayList(curr));
+        } else if (curr.size() < k) {
             for (int i = start; i < nums.length; i++) {
-                temp.add(nums[i]);
-                backtracking(k, i + 1, nums, temp, result);
-                temp.remove(temp.size() - 1);
+                curr.add(nums[i]);
+                backtracking(k, i + 1, nums, curr, result);
+                curr.remove(curr.size() - 1);
             }
         }
     }