Merge branch 'master' of https://github.com/vedantzope9/30-seconds-of…

…-java

README.md

@@ -207,6 +207,19 @@ private static void merge(int[]arr,int low,int high,int mid){
 ```
 ### LinearSearch in 2D Array
 
+```java
+public static int[] LinearSearchIn2DArray(int arr[][], int target) {
+        for (int i = 0; i < arr.length; i++) {
+            for (int j = 0; j < arr[i].length; j++) {
+                if (arr[i][j] == target)
+                    return new int[]{i, j};
+            }
+        }
+        return new int[]{-1, -1};
+    }
+```
+### LinearSearch in 2D Array
+
 ```java
 public static int[] LinearSearchIn2DArray(int arr[][], int target) {
         for (int i = 0; i < arr.length; i++) {
@@ -307,7 +320,74 @@ public static int[] BinarySearchIn2Darr(int matrix[][], int target) {
 
     }
 ```
+### BinarySearch in 2D array
+```java
+public static int[] BinarySearchIn2Darr(int matrix[][], int target) {
+        int rows = matrix.length - 1;
+        int cols = matrix[0].length - 1;
+
+        if (rows == 1) {
+            return BinarySearch(matrix, target, 0, 0, cols);
+        }
+        int rstart = 0, rend = rows;
+        int cmid = cols / 2;
+
+        //Run the loop till two rows are remaining
+        while (rstart < rend - 1)  //while this is true , we will be having more than two rows
+        {
+            int rmid = rstart + (rend - rstart) / 2;
+
+            if (matrix[rmid][cmid] > target)
+                rend = rmid;
+            else if (matrix[rmid][cmid] < target)
+                rstart = rmid;
+            else
+                return new int[]{rmid, cmid};
+        }
+        //Now we have two Rows  remaining
+
+        //1.  Check wheather middle col contains the ans
+        if (matrix[rstart][cmid] == target)
+            return new int[]{rstart, cmid};
+        if (matrix[rend][cmid] == target)
+            return new int[]{rend, cmid};
+
+        //2.Consider 4 parts  search in that parts
+
+        //search in 1st half
+        if (target <= matrix[rstart][cmid - 1])
+            return BinarySearch(matrix, target, rstart, 0, cmid - 1);
+
+        //2nd half
+        if (target >= matrix[rstart][cmid + 1])
+            return BinarySearch(matrix, target, rstart, cmid + 1, cols);
+        //3rd half
+        if (target <= matrix[rend][cmid - 1])
+            return BinarySearch(matrix, target, rend, 0, cmid - 1);
+        //4th half
+        if (target <= matrix[rend][cmid + 1])
+            return BinarySearch(matrix, target, rend, cmid + 1, cols);
+
+
+        return new int[]{-1, -1};
+    }
 
+    //Search in the specific Row provided between the col start and col end
+    static int[] BinarySearch(int matrix[][], int target, int row, int cstart, int cend) {
+        while (cstart <= cend) {
+            int cmid = cstart + (cend - cstart) / 2;
+
+            if (matrix[row][cmid] > target) {
+                cend = cmid - 1;
+            } else if (matrix[row][cmid] < target)
+                cstart = cend + 1;
+            else
+                return new int[]{row, cmid};
+        }
+        return new int[]{-1, -1};
+
+    }
+```
 ### SieveOfEratosthenes
 
 ```java
@@ -406,6 +486,28 @@ public static int[] BinarySearchIn2Darr(int matrix[][], int target) {
     }
 ```
 
+### Find mode of integer array
+
+```java
+  public static int modeArray(int arr[]) {
+        int mode = 0, maxcount = 0;
+
+        for (int i = 0; i < arr.length; i++) {
+            int count = 0;
+
+            for (int j = 0; j < arr.length; j++) {
+                if (arr[i] == arr[j])
+                    count++;
+            }
+            if (count > maxcount) {
+                maxcount = count;
+                mode = arr[i];
+            }
+        }
+        return mode;
+    }
+```
+
 ### Find sum of integer array
 
 ```java