added more problems

AlveeM · AlveeM · commit b4e6d9a905a8 · 2020-12-09T09:46:54.000-05:00
diff --git a/leetcode/top-interview-questions/01_easy_collection/09-other/01_number_of_1_bits.py b/leetcode/top-interview-questions/01_easy_collection/09-other/01_number_of_1_bits.py
@@ -0,0 +1,7 @@
+class Solution:
+    def hammingWeight(self, n: int) -> int:
+        count = 0
+        while n:
+            n &= n - 1
+            count += 1
+        return count
diff --git a/leetcode/top-interview-questions/01_easy_collection/09-other/02_hamming_distance.py b/leetcode/top-interview-questions/01_easy_collection/09-other/02_hamming_distance.py
@@ -0,0 +1,10 @@
+class Solution:
+    def hammingDistance(self, x: int, y: int) -> int:
+        x = x ^ y
+        y = 0
+        
+        while x:
+            y += 1
+            x = x & (x - 1)
+        
+        return y
diff --git a/leetcode/top-interview-questions/01_easy_collection/09-other/03_reverse_bits.py b/leetcode/top-interview-questions/01_easy_collection/09-other/03_reverse_bits.py
@@ -0,0 +1,7 @@
+class Solution:
+    def reverseBits(self, n: int) -> int:
+        res = 0
+        for _ in range(32):
+            res = (res << 1) + (n & 1)
+            n >>= 1
+        return res
diff --git a/leetcode/top-interview-questions/01_easy_collection/09-other/04_pascals_triangle.py b/leetcode/top-interview-questions/01_easy_collection/09-other/04_pascals_triangle.py
@@ -0,0 +1,11 @@
+class Solution:
+    def generate(self, numRows):
+        result = []
+        
+        for row in range(1, numRows+1):
+            row_arr = [1] * row
+            for i in range(1, row-1):
+                row_arr[i] = result[row-2][i-1] + result[row-2][i]
+            result.append(row_arr)
+        
+        return result
diff --git a/leetcode/top-interview-questions/01_easy_collection/09-other/05_valid_parenthesis.py b/leetcode/top-interview-questions/01_easy_collection/09-other/05_valid_parenthesis.py
@@ -0,0 +1,22 @@
+class Solution:
+    def isValid(self, s: str) -> bool:
+        if len(s) % 2 != 0:
+            return False
+        
+        stack = []
+        opens = ('(', '{', '[')
+        matches = (('(', ')'), ('{', '}'), ('[', ']'))
+        
+        for paren in s:
+            if paren in opens:
+                stack.append(paren)
+            else:
+                if stack:
+                    last_open = stack.pop()
+                    match = (last_open, paren)
+                    if match not in matches:
+                        return False
+                else:
+                    return False
+                
+        return len(stack) == 0
diff --git a/leetcode/top-interview-questions/01_easy_collection/09-other/06_missing_number.py b/leetcode/top-interview-questions/01_easy_collection/09-other/06_missing_number.py
@@ -0,0 +1,17 @@
+class Solution:
+    def missingNumber(self, nums):
+        i = 0
+        n = len(nums)
+        
+        while i < n:
+            j = nums[i]
+            if nums[i] < n and nums[i] != nums[j]:
+                nums[i], nums[j] = nums[j], nums[i]
+            else:
+                i += 1
+                
+        for i, num in enumerate(nums):
+            if i != num:
+                return i
+            
+        return n
diff --git a/leetcode/top-interview-questions/01_easy_collection/09-other/07_missing_number.py b/leetcode/top-interview-questions/01_easy_collection/09-other/07_missing_number.py
@@ -0,0 +1,17 @@
+class Solution:
+    def missingNumber(self, nums):
+        i = 0
+        n = len(nums)
+        
+        while i < n:
+            j = nums[i]
+            if nums[i] < n and nums[i] != nums[j]:
+                nums[i], nums[j] = nums[j], nums[i]
+            else:
+                i += 1
+                
+        for i, num in enumerate(nums):
+            if i != num:
+                return i
+            
+        return n
