diff --git a/k_diff_pairs.java b/k_diff_pairs.java
new file mode 100644
index 00000000..50812453
--- /dev/null
+++ b/k_diff_pairs.java
@@ -0,0 +1,26 @@
+class Solution {
+    public int findPairs(int[] nums, int k) {
+        HashMap<Integer,Integer> map = new HashMap<>();
+        int compl =0;
+        HashSet<List<Integer>> res = new HashSet<>();
+        for(int i=0;i<nums.length; i++) {
+            map.put(nums[i],i);
+        }
+        for(int i=0;i<nums.length;i++){
+            compl = nums[i]-k;
+            if(map.containsKey(compl)&& map.get(compl)!=i){
+                Integer[] temp = {nums[i],compl};
+                Arrays.sort(temp);
+                res.add(Arrays.asList(temp));
+            }
+            compl = nums[i]+k;
+            if(map.containsKey(compl)&& map.get(compl)!=i){
+                Integer[] temp = {nums[i],compl};
+                Arrays.sort(temp);
+                res.add(Arrays.asList(temp));
+            }
+        }
+        return res.size();
+
+    }
+}
\ No newline at end of file
diff --git a/pascals_triangle.java b/pascals_triangle.java
new file mode 100644
index 00000000..d6387859
--- /dev/null
+++ b/pascals_triangle.java
@@ -0,0 +1,25 @@
+class Solution {
+    public List<List<Integer>> generate(int numRows) {
+        List<List<Integer>> arr = new ArrayList<>();
+        List<Integer> nums2= new ArrayList<>();
+        nums2.add(1);
+        arr.add(nums2);
+        for(int i=1;i<numRows;i++){
+            List<Integer> nums= arr.get(i-1);
+            List<Integer> nums1= new ArrayList<>();
+            for(int j=0;j<=i;j++){
+                if(j==0 || j==i){
+                    nums1.add(1);
+                }else{
+                    int prev = nums.get(j-1);
+                    int next = nums.get(j);
+                    int sum = prev+next;
+                    nums1.add(sum);
+                }
+
+            }
+            arr.add(nums1);
+        }
+        return arr;
+    }
+}
\ No newline at end of file