Binary Search1 Completed

.classpath

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>

.gitignore

@@ -0,0 +1 @@
+/bin/

.project

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>BinarySearch1</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>

src/module-info.java

@@ -0,0 +1,8 @@
+/**
+ * 
+ */
+/**
+ * 
+ */
+module BinarySearch1 {
+}

src/sree/BinarySearch1.java

@@ -0,0 +1,40 @@
+package sree;
+
+class BinarySearch1 {
+    public boolean searchMatrix(int[][] matrix, int target) {
+        int m= matrix.length;
+        int n= matrix[0].length;
+
+        if (target < matrix[0][0] || target > matrix[m - 1][n - 1]) return false;
+        int low=0;
+        int high= m-1;
+        while(low<high){
+            int mid= low + (high-low)/2;
+            if(matrix[mid][n-1]== target){
+                return true;
+            }
+            else if(matrix[mid][n-1]< target){
+                low=mid+1;
+            }
+            else{
+                high=mid;
+            }
+        }
+        int row=low;
+        low=0;
+        high=n-1;
+        while(low<=high){
+            int mid=low + (high-low)/2;
+            if(matrix[row][mid]== target){
+                return true;
+            }
+            else if(matrix[row][mid]< target){
+                low= mid+1;
+            }
+            else{
+                high= mid-1;
+            }
+        }
+        return false;
+    }
+}

src/sree/BinarySearch2.java

@@ -0,0 +1,34 @@
+package sree;
+
+class BinarySearch2 {
+    public int search(int[] nums, int target) {
+        int low=0;
+        int high= nums.length-1;
+        while(low<=high){
+            int mid= low + (high-low)/2;
+            if(nums[mid]== target){
+                return mid;
+            }
+            if(nums[low]<=nums[mid]){
+                if(nums[low]<=target && nums[mid]>target){
+                    high= mid-1;
+                }
+                else{
+                    low= mid+1;
+                }
+            }
+            else 
+            {
+                if(nums[high]>=target && nums[mid]<target)
+                {
+                    low= mid+1;
+                }
+                else
+                {
+                    high=mid-1;
+                }
+            }
+        }
+        return -1;
+    }
+}

src/sree/BinarySearch3.java

@@ -0,0 +1,27 @@
+package sree;
+
+//Logic for searching in an infinitely sorted array has been using binary search.
+//Here we increase the search space by twice. and then do binary search in the required window.
+//O(log n)
+class Solution {
+    public int search( int arr[], int target) {
+        int low = 0, high = 1;
+
+        while(arr[high] < target){ 
+            low = high ;
+            high = high * 2;
+        }
+
+        while(low <= high){ 
+            int mid = low + (high - low)/2;
+            if(arr[mid] == target) return mid;
+            if(arr[mid] > target){
+                high = mid - 1;
+            }else{
+                low = mid + 1;
+            }
+        }
+
+        return -1;
+    }
+}