Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:
Integers in each row are sorted in ascending from left to right.
Integers in each column are sorted in ascending from top to bottom.
For example,
Consider the following matrix:
[[1, 4, 7, 11, 15],
[2, 5, 8, 12, 19],
[3, 6, 9, 16, 22],
[10, 13, 14, 17, 24],
[18, 21, 23, 26, 30]]
Given target = 5, return true.
Given target = 20, return false.
public class Solution {
public boolean searchMatrix(int[][] matrix, int target) {
if(matrix.length==0 || matrix[0].length==0)
return false;
int i=matrix.length-1, j=0;
while(i>=0 && j<matrix[0].length) {
int x = matrix[i][j];
if(target == x)
return true;
else if(target < x)
--i;
else ++j;
}
return false;
}
}
