Challenge 3 done

k-diff.py

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+# Time Complexity : O(NlogN)
+# Space Complexity : O(1)  
+# Did this code successfully run on Leetcode : Yes
+# Any problem you faced while coding this : No
+
+
+# Your code here along with comments explaining your approach:
+# I am sorting the array and using two pointers to find the pairs with difference k.
+# If the difference is less than k, I am moving the right pointer to increase the difference
+# If the difference is more than k, I am moving the left pointer to decrease the difference
+# If the difference is equal to k, I am adding the pair to a set to avoid duplicates and moving both pointers forward.  
+# In the end, I am returning the length of the set which contains the unique pairs.
+
+from typing import List
+class Solution:
+    def findPairs(self, nums: List[int], k: int) -> int:
+        nums.sort()
+        seen = set()
+        i = 0
+        j =  1
+        while i < len(nums) and j < len(nums):
+            if i == j or abs(nums[i] - nums[j]) < k:
+                print("j",abs(nums[i] - nums[j]))
+                j += 1
+            elif abs(nums[i] - nums[j]) > k:
+                print("i",abs(nums[i] - nums[j]))
+                i += 1
+            else:
+                seen.add((nums[i] ,nums[j]))
+                i += 1
+                j += 1
+        print(seen)
+        return len(seen)
+

pascal.py

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+# Time Complexity : O(N^2)
+# Space Complexity : O(N^2)  
+# Did this code successfully run on Leetcode : Yes
+# Any problem you faced while coding this : No
+
+
+# Your code here along with comments explaining your approach:
+# I am using a nested loop to generate the pascal triangle.
+# The outer loop is for the number of rows and the inner loop is for the number of columns.
+# I am initializing the first and last element of each row to 1.
+# For the other elements, I am adding the two elements above it to get the current element.
+# Finally, I am returning the list of lists which contains the pascal triangle.
+
+from typing import List
+class Solution:
+    def generate(self, numRows: int) -> List[List[int]]:
+        ans = []
+        for i in range(numRows):
+            r = [1] * (i+1)
+            for j in range(1,i):
+                r[j] = ans[i-1][j-1]+ans[i-1][j]
+            ans.append(r)
+        return ans
+