Search 2D Matrix

Write an efficient algorithm that searches for a value inan m x n matrix.This matrix has the following properties:

 

• Integers in each row are sortedfrom left to right.
• The first integer of each rowis greater than the last integer of the previous row.

 

For example,

Consider the following matrix:

[
  [1,   3,  5,  7],
  [10, 11, 16, 20],
  [23, 30, 34, 50]
]

Given target = 3,return true.

public class Solution {

    public booleansearchMatrix(int[][] matrix, int target) {

       // Note: The Solution object is instantiatedonly once and is reused by each test case.

       return search(matrix, 0, matrix.length-1, 0,matrix[0].length-1, target);

    }

    

    boolean search (int[][]matrix, int startRow, int endRow, int startCol, int endCol, inttarget) {

       if (endRow < startRow || endCol <startCol) {

           returnfalse;

       }

       

       int mRow = startRow + (endRow-startRow)/2;

       int mCol = startCol + (endCol-startCol)/2;

       int val = matrix[mRow][mCol];

       if (val == target) {

           returntrue;

       } else if (val > target) {

           returnsearch(matrix, startRow, endRow, startCol, mCol-1, target) //left 

              || search(matrix, startRow,mRow-1, mCol, endCol, target); // up

       } else {

           returnsearch(matrix, startRow, endRow, mCol+1, endCol, target) //right

           ||search(matrix, mRow+1, endRow, startCol, mCol, target); //below

       }

    }

}