Completed Binary-Search-1

01-Search a 2D Matrix.py

@@ -0,0 +1,40 @@
+# Problem 1 - Search a 2D Matrix (https://leetcode.com/problems/search-a-2d-matrix/)
+class Solution:
+    def searchMatrix(self, matrix: List[List[int]], target: int) -> bool:
+        # m, n = len(matrix), len(matrix[0])
+        # t = m * n
+        # l = 0
+        # r = t - 1
+
+        # while l <= r:
+        #     m = (l + r) // 2
+        #     i = m // n
+        #     j = m % n
+
+        #     mid_num = matrix[i][j]
+
+        #     if target == mid_num:
+        #         return True
+        #     elif target > mid_num:
+        #         l = m + 1
+        #     else:
+        #         r = m -1
+        # return False
+        if matrix == None or len(matrix) == 0:
+            return False
+        m = len(matrix)
+        n = len(matrix[0])
+        low = 0
+        high = m * n - 1
+
+        while low <= high:
+            mid = low + (high - low) // 2
+            row = mid // n
+            col = mid % n
+            if matrix[row][col] == target:
+                return True
+            elif matrix[row][col] < target:
+                low = mid + 1
+            else:
+                high = mid - 1
+        return False

02-Search in Rotated Sorted Array.py

@@ -0,0 +1,28 @@
+# Problem 2 - Search in Rotated Sorted Array (https://leetcode.com/problems/search-in-rotated-sorted-array/)
+class Solution:
+    def search(self, nums: List[int], target: int) -> int:
+        if nums == None or len(nums) == 0:
+            return -1
+
+        n = len(nums)
+        low = 0
+        high = n - 1
+
+        while low <= high:
+            mid = (low + high) // 2
+            if nums[mid] == target:
+                return mid
+            # left sorted
+            if nums[low] <= nums[mid]:
+                # check if num lies in sorted part
+                if nums[low] <= target and nums[mid] > target:
+                    high = mid - 1
+                else:
+                    low = mid + 1
+            # right sorted
+            else:
+                if nums[mid] < target and nums[high] >= target:
+                    low = mid + 1
+                else:
+                    high = mid - 1
+        return -1

03-Search in a Sorted Array of Unknown Size.py

@@ -0,0 +1,27 @@
+# Search in a Sorted Array of Unknown Size (https://leetcode.com/problems/search-in-a-sorted-array-of-unknown-size/)
+# """
+# This is ArrayReader's API interface.
+# You should not implement it, or speculate about its implementation
+# """
+#class ArrayReader:
+#    def get(self, index: int) -> int:
+
+class Solution:
+    def search(self, reader: 'ArrayReader', target: int) -> int:
+        low = 0
+        high = 1
+
+        while reader.get(high) < target:
+            low = high
+            high = 2 * high
+
+        while low <= high:
+            mid = (low + high) // 2
+            if reader.get(mid) == target:
+                return mid
+            elif reader.get(mid) < target:
+                low = mid + 1
+            else:
+                high = mid - 1
+
+        return -1