Create 40-Combination-Sum-II.java

Author: SharmaTushar1

java/40-Combination-Sum-II.java

@@ -0,0 +1,25 @@
+class Solution {
+    public List<List<Integer>> combinationSum2(int[] candidates, int target) {
+        Arrays.sort(candidates);
+        List<List<Integer>> ans = new ArrayList<List<Integer>>();
+        List<Integer> ls = new ArrayList<Integer>();
+        comb(candidates, target, ans, ls, 0);
+        return ans;
+    }
+    
+    public void comb(int[] candidates, int target, List<List<Integer>> ans, List<Integer> ls, int index) {
+        if (target == 0) {
+            ans.add(new ArrayList(ls));
+        }
+        else if (target<0) 
+            return;
+        else {
+            for (int i = index; i<candidates.length; i++) {
+                if(i>index && candidates[i] == candidates[i-1]) continue;
+                ls.add(candidates[i]);
+                comb(candidates, target-candidates[i], ans, ls, i+1);
+                ls.remove(ls.get(ls.size()-1));
+            }
+        }
+    }
+}