diff --git a/KDiffPairs.java b/KDiffPairs.java
new file mode 100644
index 00000000..fecaf4f2
--- /dev/null
+++ b/KDiffPairs.java
@@ -0,0 +1,38 @@
+
+// 532. K-diff Pairs in an Array
+// https://leetcode.com/problems/k-diff-pairs-in-an-array/description/
+
+/**
+ * Time Complexity: O(n) since we iterate over each element
+ * Space Complexity: O(n) since in worst case we store all elements
+ */
+
+class Solution {
+    public int findPairs(int[] nums, int k) {
+        Map<Integer, Integer> map = new HashMap<>();
+
+        int count = 0;
+
+        for(int num : nums){ // count frequency of numbers
+            map.put(num, map.getOrDefault(num, 0) + 1);
+        }
+
+        for(int num : map.keySet()){ // iterating on keys as we want unique pairs
+
+            int anotherNumber = num + k;
+
+            // if k is 0, we need to check if the same number exists more than once as we cannot consider same number
+            if(k == 0){ 
+               if(map.get(anotherNumber) > 1){ 
+                    count++;
+               }
+            }else{
+               if(map.containsKey(anotherNumber)){
+                    count++;
+               }                
+            }
+        }
+
+        return count;
+    }
+}
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diff --git a/PascalsTriangle.java b/PascalsTriangle.java
new file mode 100644
index 00000000..489b9dbf
--- /dev/null
+++ b/PascalsTriangle.java
@@ -0,0 +1,37 @@
+// 118. Pascal's Triangle
+// https://leetcode.com/problems/pascals-triangle/description/
+
+/**
+ * Time Complexity: O(n * m) ~ O(n^2) since we iterate over each element
+ * Space Complexity: O(1) since no auxillary space as we dont consider result 
+ */
+
+
+
+class Solution {
+    public List<List<Integer>> generate(int numRows) {
+        List<List<Integer>> result = new ArrayList<>();
+
+        for(int i = 0 ; i < numRows ; i++){
+
+            List<Integer> currList = new ArrayList<>();
+
+            for(int j = 0 ; j <= i ; j++){
+
+                if(j == 0 || j == i){
+                    currList.add(1);
+                }else{
+                    List<Integer> prevList = result.get(i - 1);
+
+                    int currNumber = prevList.get(j - 1) + prevList.get(j);
+
+                    currList.add(currNumber);
+                }
+            }
+
+            result.add(currList);
+        }
+
+        return result;
+    }
+}
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