Binary-Search-1 Solution

problem1Solution.java

@@ -0,0 +1,30 @@
+//Time Complexity : O(log n)
+//Space Complexity : O(1)
+//Search in a Rotated Sorted Array
+
+public class problem1Solution {
+    public int search(int[] nums, int target) {
+        int left = 0;
+        int right = nums.length-1;
+        while(left<=right){
+            int mid = left + (right - left)/2;
+            if(nums[mid]== target) return mid;
+            if(nums[left]<=nums[mid]) {
+                if (target > nums[mid] || target < nums[left] )
+                    left = mid + 1;
+                else {
+                    right = mid -1;
+                }
+            }
+            else {
+                if( target < nums[mid] || target > nums[right]){
+                    right = mid - 1;
+                }
+                else {
+                    left = mid + 1;
+                }
+            }
+        }
+        return -1;
+    }
+}

problem2Solution.java

@@ -0,0 +1,25 @@
+//Time complexity : O(log n)
+//Space complexity : O(1)
+//Search Inside a Sorted Array whose Length is unknown
+
+public class problem2Solution {
+    public int search(ArrayReader reader, int target) {
+        int left = 0;
+        int right = 1;
+        while(reader.get(right) <= target) {
+            left = right;
+            right = 2*right;
+        }
+
+        while(left <= right) {
+            int mid = left + (right - left)/2;
+            if(reader.get(mid) == target) return mid;
+            if(reader.get(mid) < target) {
+                left = mid + 1;
+            } else {
+                right = mid - 1;
+            }
+        }
+        return -1;
+    }
+}

problem3Solution.java

@@ -0,0 +1,28 @@
+//Time Complexity : O(log m*n)
+//Space Complexity : O(1)
+//Search a 2D Matrix
+public class problem3Solution {
+    public boolean searchMatrix(int[][] matrix, int target) {
+        int r = matrix.length;
+        int c = matrix[0].length;
+
+        int left = 0;
+        int right = (r*c)-1;
+
+        while (left <= right) {
+            int mid = left + (right - left)/2;
+            int midRow = mid/c;
+            int midCol = mid%c;
+            if(matrix[midRow][midCol]== target) {
+                return true;
+            }
+            else if(matrix[midRow][midCol]< target) {
+                left = mid+1;
+            }
+            else {
+                right = mid-1;
+            }
+        }
+        return false;
+    }
+}