法1:二分搜索
剑指原题
java
class Solution {
public boolean searchMatrix(int[][] matrix, int target) {
int m = matrix.length, n = matrix[0].length;
int i = 0, j = n - 1;
while (i < m && j >= 0) {
if (matrix[i][j] == target) {
return true;
} else if (matrix[i][j] < target) {
++i;
} else {
--j;
}
}
return false;
}
}