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feat: add python and java solutions to lcci question
添加《程序员面试金典》题解：面试题 10.09. 排序矩阵查找
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‎lcci/10.09.Sorted Matrix Search/README.md

+35-2
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@@ -24,20 +24,53 @@
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## 解法
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<!-- 这里可写通用的实现逻辑 -->
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从左下角（或右上角）开始查找即可。
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### Python3
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
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class Solution:
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def searchMatrix(self, matrix: List[List[int]], target: int) -> bool:
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if not matrix or not matrix[0]:
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return False
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rows, cols = len(matrix), len(matrix[0])
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i, j = rows - 1, 0
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while i >= 0 and j < cols:
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if matrix[i][j] == target:
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return True
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if matrix[i][j] > target:
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i -= 1
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else:
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j += 1
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return False
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```
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### Java
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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class Solution {
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public boolean searchMatrix(int[][] matrix, int target) {
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if (matrix == null || matrix.length == 0 || matrix[0] == null || matrix[0].length == 0) {
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return false;
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}
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int rows = matrix.length, cols = matrix[0].length;
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int i = rows - 1, j = 0;
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while (i >= 0 && j < cols) {
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if (matrix[i][j] == target) {
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return true;
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}
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if (matrix[i][j] > target) {
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--i;
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} else {
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++j;
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}
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}
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return false;
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}
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}
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```
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### ...

‎lcci/10.09.Sorted Matrix Search/README_EN.md

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Original file line numberDiff line numberDiff line change
@@ -1,44 +1,96 @@
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# [10.09. Sorted Matrix Search](https://leetcode-cn.com/problems/sorted-matrix-search-lcci)
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## Description
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<p>Given an M x N matrix in which each row and each column is sorted in ascending order, write a method to find an element.</p>
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<p><strong>Example:</strong></p>
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<p>Given matrix:</p>
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<pre>
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[
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[1, 4, 7, 11, 15],
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[2, 5, 8, 12, 19],
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[3, 6, 9, 16, 22],
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[10, 13, 14, 17, 24],
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[18, 21, 23, 26, 30]
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]
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</pre>
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<p>Given target&nbsp;=&nbsp;5,&nbsp;return&nbsp;<code>true.</code></p>
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<p>Given target&nbsp;=&nbsp;20, return&nbsp;<code>false.</code></p>
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## Solutions
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### Python3
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```python
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```
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### Java
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```java
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```
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### ...
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```
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```
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# [10.09. Sorted Matrix Search](https://leetcode-cn.com/problems/sorted-matrix-search-lcci)
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## Description
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<p>Given an M x N matrix in which each row and each column is sorted in ascending order, write a method to find an element.</p>
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<p><strong>Example:</strong></p>
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<p>Given matrix:</p>
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<pre>
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[
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[1, 4, 7, 11, 15],
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[2, 5, 8, 12, 19],
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[3, 6, 9, 16, 22],
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[10, 13, 14, 17, 24],
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[18, 21, 23, 26, 30]
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]
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</pre>
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<p>Given target&nbsp;=&nbsp;5,&nbsp;return&nbsp;<code>true.</code></p>
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<p>Given target&nbsp;=&nbsp;20, return&nbsp;<code>false.</code></p>
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## Solutions
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### Python3
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```python
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class Solution:
52+
def searchMatrix(self, matrix: List[List[int]], target: int) -> bool:
53+
if not matrix or not matrix[0]:
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return False
55+
rows, cols = len(matrix), len(matrix[0])
56+
i, j = rows - 1, 0
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while i >= 0 and j < cols:
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if matrix[i][j] == target:
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return True
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if matrix[i][j] > target:
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i -= 1
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else:
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j += 1
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return False
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```
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### Java
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```java
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class Solution {
72+
public boolean searchMatrix(int[][] matrix, int target) {
73+
if (matrix == null || matrix.length == 0 || matrix[0] == null || matrix[0].length == 0) {
74+
return false;
75+
}
76+
int rows = matrix.length, cols = matrix[0].length;
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int i = rows - 1, j = 0;
78+
while (i >= 0 && j < cols) {
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if (matrix[i][j] == target) {
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return true;
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}
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if (matrix[i][j] > target) {
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--i;
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} else {
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++j;
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}
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}
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return false;
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}
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}
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```
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### ...
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```
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```

‎lcci/10.09.Sorted Matrix Search/Solution.java

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@@ -0,0 +1,20 @@
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class Solution {
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public boolean searchMatrix(int[][] matrix, int target) {
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if (matrix == null || matrix.length == 0 || matrix[0] == null || matrix[0].length == 0) {
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return false;
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}
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int rows = matrix.length, cols = matrix[0].length;
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int i = rows - 1, j = 0;
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while (i >= 0 && j < cols) {
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if (matrix[i][j] == target) {
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return true;
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}
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if (matrix[i][j] > target) {
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--i;
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} else {
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++j;
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}
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}
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return false;
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}
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}

‎lcci/10.09.Sorted Matrix Search/Solution.py

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@@ -0,0 +1,14 @@
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class Solution:
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def searchMatrix(self, matrix: List[List[int]], target: int) -> bool:
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if not matrix or not matrix[0]:
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return False
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rows, cols = len(matrix), len(matrix[0])
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i, j = rows - 1, 0
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while i >= 0 and j < cols:
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if matrix[i][j] == target:
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return True
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if matrix[i][j] > target:
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i -= 1
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else:
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j += 1
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return False

‎lcof/面试题04. 二维数组中的查找/README.md

+12-12
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@@ -34,38 +34,38 @@
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```python
3535
class Solution:
3636
def findNumberIn2DArray(self, matrix: List[List[int]], target: int) -> bool:
37-
if not matrix:
37+
if not matrix or not matrix[0]:
3838
return False
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40-
i, j = len(matrix) - 1, 0
41-
while i >= 0 and j < len(matrix[0]):
39+
rows, cols = len(matrix), len(matrix[0])
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i, j = rows - 1, 0
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while i >= 0 and j < cols:
4242
if matrix[i][j] == target:
4343
return True
44-
if matrix[i][j] < target:
45-
j += 1
46-
else:
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if matrix[i][j] > target:
4745
i -= 1
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else:
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j += 1
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return False
49+
4950
```
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### Java
5253
```java
5354
class Solution {
5455
public boolean findNumberIn2DArray(int[][] matrix, int target) {
55-
if (matrix == null || matrix.length == 0) {
56+
if (matrix == null || matrix.length == 0 || matrix[0] == null || matrix[0].length == 0) {
5657
return false;
5758
}
5859
int rows = matrix.length, cols = matrix[0].length;
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int i = rows - 1, j = 0;
6161
while (i >= 0 && j < cols) {
6262
if (matrix[i][j] == target) {
6363
return true;
6464
}
65-
if (matrix[i][j] < target) {
66-
++j;
67-
} else {
65+
if (matrix[i][j] > target) {
6866
--i;
67+
} else {
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++j;
6969
}
7070
}
7171
return false;

‎lcof/面试题04. 二维数组中的查找/Solution.java

+4-5
Original file line numberDiff line numberDiff line change
@@ -1,19 +1,18 @@
11
class Solution {
22
public boolean findNumberIn2DArray(int[][] matrix, int target) {
3-
if (matrix == null || matrix.length == 0) {
3+
if (matrix == null || matrix.length == 0 || matrix[0] == null || matrix[0].length == 0) {
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return false;
55
}
66
int rows = matrix.length, cols = matrix[0].length;
7-
87
int i = rows - 1, j = 0;
98
while (i >= 0 && j < cols) {
109
if (matrix[i][j] == target) {
1110
return true;
1211
}
13-
if (matrix[i][j] < target) {
14-
++j;
15-
} else {
12+
if (matrix[i][j] > target) {
1613
--i;
14+
} else {
15+
++j;
1716
}
1817
}
1918
return false;

‎lcof/面试题04. 二维数组中的查找/Solution.py

+8-8
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@@ -1,14 +1,14 @@
11
class Solution:
22
def findNumberIn2DArray(self, matrix: List[List[int]], target: int) -> bool:
3-
if not matrix:
3+
if not matrix or not matrix[0]:
44
return False
5-
6-
i, j = len(matrix) - 1, 0
7-
while i >= 0 and j < len(matrix[0]):
5+
rows, cols = len(matrix), len(matrix[0])
6+
i, j = rows - 1, 0
7+
while i >= 0 and j < cols:
88
if matrix[i][j] == target:
99
return True
10-
if matrix[i][j] < target:
11-
j += 1
12-
else:
10+
if matrix[i][j] > target:
1311
i -= 1
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return False
12+
else:
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j += 1
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return False

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