Write an efficient algorithm that searches for a value target in an m x n integer matrix 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.
二维矩阵的搜索策略 ， 从最后一行的行首开始搜索 （保证大或者小的行走方向唯一） 如果遇到小于target的元素 ， 向右走一行 如果遇到大于target的元素 ， 向上走一行 如果遇到等于target的元素，向上走一行 + 向右走一行
impl Solution {
pub fn search_matrix(matrix: Vec<Vec<i32>>, target: i32) -> bool {
let row_size = matrix.len();
let col_size = matrix[0].len();
let mut r = row_size as i32 - 1;
let mut c = 0_i32;
while r >= 0 && c < col_size as i32 {
// 最后一层，最左侧
if matrix[r as usize][c as usize] < target {
c += 1;
} else if matrix[r as usize][c as usize] > target {
r -= 1;
} else {
c += 1;
r -= 1;
return true;
}
}
false
}
}