The basic idea is from right corner, if the current number greater than target col - 1 in same row, else if the current number less than target, row + 1 in same column, finally if they are same, we find it, and return return.

```
public boolean searchMatrix(int[][] matrix, int target) {
int i = 0, j = matrix[0].length - 1;
while (i < matrix.length && j >= 0) {
if (matrix[i][j] == target) {
return true;
} else if (matrix[i][j] > target) {
j--;
} else {
i++;
}
}
return false;
}
```