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feat: add solutions to lc problem: No.1352
No.1352.Product of the Last K Numbers
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‎solution/1300-1399/1351.Count Negative Numbers in a Sorted Matrix/README.md

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Original file line numberDiff line numberDiff line change
@@ -48,15 +48,19 @@
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根据**其行列都以非递增顺序排列**的特点，可以从**左下角**开始**往右上方向遍历**。
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当遇到负数时，说明这一行从当前位置开始往右的所有元素均为负数，那么 `ans += n - j`，并且 i 指针上移；否则 j 指针右移。遍历结束，返回 `ans`。
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当遇到负数时，说明这一行从当前位置开始往右的所有元素均为负数，我们将答案加上这一行剩余的元素个数，即 $n - j$，并且向上移动一行，即 $i \leftarrow i - 1$。否则，向右移动一列，即 $j \leftarrow j + 1$。
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时间复杂度：$O(m + n)$。
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遍历结束，返回答案。
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时间复杂度 $O(m + n)$。其中 $m$ 和 $n$ 分别为矩阵的行数和列数。
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**方法二：二分查找**
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遍历每一行，查找每一行第一个小于 0 的位置，从该位置开始往右的所有元素均为负数，累加负数个数到 `ans`。遍历结束，返回 `ans`。
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遍历每一行，二分查找每一行第一个小于 $0$ 的位置，从该位置开始往右的所有元素均为负数，累加负数个数到答案中。
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遍历结束，返回答案。
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时间复杂度：$O(mlogn)$。
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时间复杂度 $O(m \times \log n)$。其中 $m$ 和 $n$ 分别为矩阵的行数和列数。
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<!-- tabs:start -->
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@@ -82,18 +86,7 @@ class Solution:
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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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ans = 0
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n = len(grid[0])
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for row in grid:
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left, right = 0, n
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while left < right:
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mid = (left + right) >> 1
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if row[mid] < 0:
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right = mid
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else:
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left = mid + 1
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ans += n - left
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return ans
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return sum(bisect_left(row[::-1], 0) for row in grid)
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```
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### **Java**
@@ -140,46 +133,6 @@ class Solution {
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}
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```
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### **TypeScript**
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```ts
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function countNegatives(grid: number[][]): number {
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const m = grid.length,
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n = grid[0].length;
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let ans = 0;
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for (let i = m - 1, j = 0; i >= 0 && j < n; ) {
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if (grid[i][j] < 0) {
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ans += n - j;
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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 ans;
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}
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```
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```ts
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function countNegatives(grid: number[][]): number {
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const n = grid[0].length;
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let ans = 0;
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for (let row of grid) {
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let left = 0,
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right = n;
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while (left < right) {
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const mid = (left + right) >> 1;
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if (row[mid] < 0) {
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right = mid;
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} else {
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left = mid + 1;
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}
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}
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ans += n - left;
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}
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return ans;
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}
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```
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### **C++**
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```cpp
@@ -205,17 +158,8 @@ class Solution {
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public:
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int countNegatives(vector<vector<int>>& grid) {
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int ans = 0;
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int n = grid[0].size();
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for (auto& row : grid)
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{
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int left = 0, right = n;
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while (left < right)
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{
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int mid = (left + right) >> 1;
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if (row[mid] < 0) right = mid;
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else left = mid + 1;
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}
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ans += n - left;
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for (auto& row : grid) {
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ans += lower_bound(row.rbegin(), row.rend(), 0) - row.rbegin();
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}
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return ans;
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}
@@ -259,6 +203,46 @@ func countNegatives(grid [][]int) int {
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}
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```
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### **TypeScript**
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```ts
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function countNegatives(grid: number[][]): number {
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const m = grid.length,
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n = grid[0].length;
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let ans = 0;
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for (let i = m - 1, j = 0; i >= 0 && j < n; ) {
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if (grid[i][j] < 0) {
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ans += n - j;
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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 ans;
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}
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```
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```ts
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function countNegatives(grid: number[][]): number {
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const n = grid[0].length;
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let ans = 0;
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for (let row of grid) {
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let left = 0,
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right = n;
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while (left < right) {
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const mid = (left + right) >> 1;
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if (row[mid] < 0) {
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right = mid;
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} else {
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left = mid + 1;
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}
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}
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ans += n - left;
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}
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return ans;
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}
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```
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### **JavaScript**
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```js

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

Lines changed: 43 additions & 63 deletions
Original file line numberDiff line numberDiff line change
@@ -59,18 +59,7 @@ class Solution:
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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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ans = 0
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n = len(grid[0])
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for row in grid:
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left, right = 0, n
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while left < right:
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mid = (left + right) >> 1
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if row[mid] < 0:
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right = mid
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else:
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left = mid + 1
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ans += n - left
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return ans
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return sum(bisect_left(row[::-1], 0) for row in grid)
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```
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### **Java**
@@ -115,46 +104,6 @@ class Solution {
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}
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```
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### **TypeScript**
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```ts
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function countNegatives(grid: number[][]): number {
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const m = grid.length,
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n = grid[0].length;
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let ans = 0;
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for (let i = m - 1, j = 0; i >= 0 && j < n; ) {
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if (grid[i][j] < 0) {
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ans += n - j;
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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 ans;
134-
}
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```
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```ts
138-
function countNegatives(grid: number[][]): number {
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const n = grid[0].length;
140-
let ans = 0;
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for (let row of grid) {
142-
let left = 0,
143-
right = n;
144-
while (left < right) {
145-
const mid = (left + right) >> 1;
146-
if (row[mid] < 0) {
147-
right = mid;
148-
} else {
149-
left = mid + 1;
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}
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}
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ans += n - left;
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}
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return ans;
155-
}
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```
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158107
### **C++**
159108

160109
```cpp
@@ -180,17 +129,8 @@ class Solution {
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public:
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int countNegatives(vector<vector<int>>& grid) {
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int ans = 0;
183-
int n = grid[0].size();
184-
for (auto& row : grid)
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{
186-
int left = 0, right = n;
187-
while (left < right)
188-
{
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int mid = (left + right) >> 1;
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if (row[mid] < 0) right = mid;
191-
else left = mid + 1;
192-
}
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ans += n - left;
132+
for (auto& row : grid) {
133+
ans += lower_bound(row.rbegin(), row.rend(), 0) - row.rbegin();
194134
}
195135
return ans;
196136
}
@@ -234,6 +174,46 @@ func countNegatives(grid [][]int) int {
234174
}
235175
```
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177+
### **TypeScript**
178+
179+
```ts
180+
function countNegatives(grid: number[][]): number {
181+
const m = grid.length,
182+
n = grid[0].length;
183+
let ans = 0;
184+
for (let i = m - 1, j = 0; i >= 0 && j < n; ) {
185+
if (grid[i][j] < 0) {
186+
ans += n - j;
187+
--i;
188+
} else {
189+
++j;
190+
}
191+
}
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return ans;
193+
}
194+
```
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```ts
197+
function countNegatives(grid: number[][]): number {
198+
const n = grid[0].length;
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let ans = 0;
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for (let row of grid) {
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let left = 0,
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right = n;
203+
while (left < right) {
204+
const mid = (left + right) >> 1;
205+
if (row[mid] < 0) {
206+
right = mid;
207+
} else {
208+
left = mid + 1;
209+
}
210+
}
211+
ans += n - left;
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}
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return ans;
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}
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```
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### **JavaScript**
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```js

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