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feat: add solutions to lc problem: No.1351. Count Negative Numbers in a Sorted Matrix
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‎solution/1300-1399/1351.Count Negative Numbers in a Sorted Matrix/README.md

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<p> </p>
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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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从右上角开始遍历。当遇到负数时，说明这一列从当前行往下的所有数（共 `m - i` 个数）均为负数，`cnt += (m - i)`，然后 j 往左移动一个位置。否则 i 往下移动一个位置。
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最后返回 cnt 值即可。
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<!-- tabs:start -->
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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 countNegatives(self, grid: List[List[int]]) -> int:
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m, n, cnt = len(grid), len(grid[0]), 0
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i, j = 0, n - 1
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while i < m and j >= 0:
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if grid[i][j] < 0:
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cnt += (m - i)
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j -= 1
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else:
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i += 1
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return cnt
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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 int countNegatives(int[][] grid) {
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int m = grid.length, n = grid[0].length;
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int cnt = 0;
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for (int i = 0, j = n - 1; j >= 0 && i < m;) {
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if (grid[i][j] < 0) {
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cnt += (m - i);
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--j;
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} else {
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++i;
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}
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}
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return cnt;
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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int countNegatives(vector<vector<int>>& grid) {
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int m = grid.size(), n = grid[0].size();
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int i = 0, j = n - 1, cnt = 0;
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while (i < m && j >= 0) {
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if (grid[i][j] < 0) {
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cnt += (m - i);
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--j;
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} else {
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++i;
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}
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}
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return cnt;
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}
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};
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```
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### **Go**
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```go
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func countNegatives(grid [][]int) int {
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m, n := len(grid), len(grid[0])
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i, j, cnt := 0, n-1, 0
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for i < m && j >= 0 {
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if grid[i][j] < 0 {
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cnt += (m - i)
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j--
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} else {
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i++
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}
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}
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return cnt
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}
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```
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### **...**

‎solution/1300-1399/1351.Count Negative Numbers in a Sorted Matrix/README_EN.md

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### **Python3**
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```python
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class Solution:
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def countNegatives(self, grid: List[List[int]]) -> int:
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m, n, cnt = len(grid), len(grid[0]), 0
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i, j = 0, n - 1
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while i < m and j >= 0:
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if grid[i][j] < 0:
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cnt += (m - i)
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j -= 1
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else:
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i += 1
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return cnt
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```
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### **Java**
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```java
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class Solution {
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public int countNegatives(int[][] grid) {
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int m = grid.length, n = grid[0].length;
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int cnt = 0;
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for (int i = 0, j = n - 1; j >= 0 && i < m;) {
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if (grid[i][j] < 0) {
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cnt += (m - i);
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--j;
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} else {
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++i;
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}
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}
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return cnt;
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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int countNegatives(vector<vector<int>>& grid) {
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int m = grid.size(), n = grid[0].size();
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int i = 0, j = n - 1, cnt = 0;
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while (i < m && j >= 0) {
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if (grid[i][j] < 0) {
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cnt += (m - i);
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--j;
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} else {
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++i;
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}
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}
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return cnt;
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}
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};
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```
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### **Go**
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```go
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func countNegatives(grid [][]int) int {
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m, n := len(grid), len(grid[0])
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i, j, cnt := 0, n-1, 0
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for i < m && j >= 0 {
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if grid[i][j] < 0 {
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cnt += (m - i)
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j--
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} else {
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i++
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}
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}
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return cnt
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}
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```
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### **...**

‎solution/1300-1399/1351.Count Negative Numbers in a Sorted Matrix/Solution.cpp

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class Solution {
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public:
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int countNegatives(vector<vector<int>>& grid) {
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int m = grid.size(), n = grid[0].size();
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int i = 0, j = n - 1, cnt = 0;
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while (i < m && j >= 0) {
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if (grid[i][j] < 0) {
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cnt += (m - i);
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--j;
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} else {
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++i;
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}
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}
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return cnt;
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}
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};

‎solution/1300-1399/1351.Count Negative Numbers in a Sorted Matrix/Solution.go

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func countNegatives(grid [][]int) int {
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m, n := len(grid), len(grid[0])
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i, j, cnt := 0, n-1, 0
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for i < m && j >= 0 {
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if grid[i][j] < 0 {
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cnt += (m - i)
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j--
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} else {
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i++
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}
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}
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return cnt
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}

‎solution/1300-1399/1351.Count Negative Numbers in a Sorted Matrix/Solution.java

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class Solution {
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public int countNegatives(int[][] grid) {
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int m = grid.length, n = grid[0].length;
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int cnt = 0;
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for (int i = 0, j = n - 1; j >= 0 && i < m;) {
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if (grid[i][j] < 0) {
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cnt += (m - i);
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--j;
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} else {
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++i;
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}
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}
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return cnt;
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}
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}

‎solution/1300-1399/1351.Count Negative Numbers in a Sorted Matrix/Solution.py

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class Solution:
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def countNegatives(self, grid: List[List[int]]) -> int:
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m, n, cnt = len(grid), len(grid[0]), 0
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i, j = 0, n - 1
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while i < m and j >= 0:
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if grid[i][j] < 0:
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cnt += (m - i)
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j -= 1
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else:
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i += 1
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return cnt

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